+publisher:"University of Saskatchewan" +contributor:("Clark, Robert G.")

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1. Crane, Adam 1980-. Social learning of predation risk and safety: fish behaviour as a model for fear recovery.

Degree: 2017, University of Saskatchewan

URL: http://hdl.handle.net/10388/8166

► As animal behaviour theory has developed over the past 70 years, much attention has gone toward social information use. Social cues in a variety of… (more)

▼ As animal behaviour theory has developed over the past 70 years, much attention has gone toward social information use. Social cues in a variety of forms can be critically important in finding food and mates, in defending territories, and in avoiding predators. A wide variety of prey species are capable of learning from social information regarding predation threats, but little attention has gone toward factors that influence the acquisition of such information, how it compares to other learning mechanisms, or how prey learn socially about the absence of risk. Herein, I present research with fathead minnows, Pimephales promelas, where I first showed that learned fear responses were similar between social learning and individual learning, but socially-acquired information was more persuasive and had an overriding effect on previously learned safety. Using repeated exposures to general predation cues that lacked specific information about the predator’s identity, I induced uncertainty in naïve individuals (observers) or in knowledgeable individuals (models) within a social pairing. Repeated exposure to risk, regardless of uncertainty, promoted a high-risk phenotype that was characterized by propensity to freeze, stereotypic route-tracing, and neophobia – a phenomenon where animals show generalized fear responses toward novel stimuli. Attempting to weaken this phenotype, I paired high-risk individuals with models that were experienced with an odour as safe, but a single conditioning with one ‘safety model’ had little effect. Instead, interacting with high-risk individuals caused models to indirectly acquire the high-risk phenotype. Hence, this social transfer of information caused models to behave fearfully, making them poor demonstrators of safety. To counteract this, I used groups of calm models, or multiple, individual calm models in succession. Both strategies weakened fear in observers, as well as socially-transferred fear in models, but surprisingly this effect was much stronger among individuals exposed to risk in isolation, despite their tendency for stronger neophobia initially. While our basic knowledge of social systems has grown substantially in recent years, rarely has it been applied to human issues. My work bridges animal behaviour theory and human psychology, arguing that our understanding of predation-related fear and the information transfer in social animals can prove fruitful in understanding post-traumatic stress and behavioural therapy for its recovery. Advisors/Committee Members: Ferrari, Maud C.O., Chivers, Douglas P., Clark, Robert G., Stookey, Joeseph M., Benson, James D..

Subjects/Keywords: alarm cue; fright; minnow; neophobia; PTSD

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APA (6^th Edition):

Crane, A. 1. (2017). Social learning of predation risk and safety: fish behaviour as a model for fear recovery. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/8166

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Crane, Adam 1980-. “Social learning of predation risk and safety: fish behaviour as a model for fear recovery.” 2017. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/8166.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Crane, Adam 1980-. “Social learning of predation risk and safety: fish behaviour as a model for fear recovery.” 2017. Web. 18 Jan 2021.

Vancouver:

Crane A1. Social learning of predation risk and safety: fish behaviour as a model for fear recovery. [Internet] [Thesis]. University of Saskatchewan; 2017. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/8166.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Crane A1. Social learning of predation risk and safety: fish behaviour as a model for fear recovery. [Thesis]. University of Saskatchewan; 2017. Available from: http://hdl.handle.net/10388/8166

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

2. Elgin, Andrew Stephen 1994-. CONSERVING PRAIRIE PONDS FOR SWALLOWS: TREE SWALLOW (TACHYCINETA BICOLOR) FORAGING AND NESTLING DIET QUALITY IN PRAIRIE AGROECOSYSTEMS.

Degree: 2019, University of Saskatchewan

URL: http://hdl.handle.net/10388/12471

► Wetland ponds in the Prairie Pothole Region (PPR) of North America are foraging habitat for many avian species; however, the PPR is also agriculturally intensive… (more)

▼ Wetland ponds in the Prairie Pothole Region (PPR) of North America are foraging habitat for many avian species; however, the PPR is also agriculturally intensive and expansive, containing most of the cropland in Canada. Tree Swallows (Tachycineta bicolor), among other swallows and martins (Family Hirundinidae), forage over ponds and other aquatic habitats to exploit emergent aquatic insects as prey. Swallows may benefit from sources of aquatic insect prey, but they may incur costs, such as pesticide exposure, when foraging in landscapes dominated by cultivated cropland. I investigated the importance of ponds as foraging areas and a factor in insect prey quality for Tree Swallows nesting in prairie agroecosystems. I examined breeding female swallows’ foraging habitat selection as well as nestling swallows’ omega-3 long-chain polyunsaturated fatty acid (LC-PUFA) status and exposure to neonicotinoid insecticides – two indicators of nestling diet quality potentially influenced by prairie ponds. Based on data from GPS-tagging and a resource selection function (RSF) statistical approach, I found that female swallows more strongly selected for ponds relative to terrestrial habitats. There was a statistically significant increase in relative selection for ponds with distance from the nest, consistent with an energetic trade-off between travelling and use of more profitable foraging patches. I used the ratio of eicosapentaenoic acid (EPA, an omega-3 LC-PUFA) to arachidonic acid (ARA, an omega-6 LC-PUFA) as a qualitative dietary tracer and indicator of omega-3 LC-PUFA intake for swallows. Differences between sites in swallow erythrocyte EPA:ARA ratios were consistent with possible differences in aquatic insect biomass, unrelated to the presence of cropping. Widespread exposure to neonicotinoid insecticides was confirmed via analysis of blood plasma from nestling and adult swallows. Swallows on different study sites differed in exposure, but nestling plasma concentrations of imidacloprid were not strongly associated with amount of cropped area near nests. Nestlings hatched near cultivated cropland had greater plasma concentrations of clothianidin, on average, than those on a grassland-dominated site. Finally, an increase in nestling erythrocyte EPA:ARA ratio was associated with an increase in nestling mass, while no association between plasma total neonicotinoid concentrations and mass was detected. These results have implications for the conservation of aerial insectivores and suggest the importance of conserving and restoring prairie ponds in agroecosystems to ensure the maintenance of biodiversity in the PPR. Advisors/Committee Members: Morrissey, Christy A, Clark, Robert G, Jardine, Timothy D, Marchant, Tracy A, Kraus, Johanna M.

Subjects/Keywords: swallows; aerial insectivores; birds; ponds; prairie; potholes; wetlands; agriculture

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APA (6^th Edition):

Elgin, A. S. 1. (2019). CONSERVING PRAIRIE PONDS FOR SWALLOWS: TREE SWALLOW (TACHYCINETA BICOLOR) FORAGING AND NESTLING DIET QUALITY IN PRAIRIE AGROECOSYSTEMS. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12471

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Elgin, Andrew Stephen 1994-. “CONSERVING PRAIRIE PONDS FOR SWALLOWS: TREE SWALLOW (TACHYCINETA BICOLOR) FORAGING AND NESTLING DIET QUALITY IN PRAIRIE AGROECOSYSTEMS.” 2019. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/12471.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Elgin, Andrew Stephen 1994-. “CONSERVING PRAIRIE PONDS FOR SWALLOWS: TREE SWALLOW (TACHYCINETA BICOLOR) FORAGING AND NESTLING DIET QUALITY IN PRAIRIE AGROECOSYSTEMS.” 2019. Web. 18 Jan 2021.

Vancouver:

Elgin AS1. CONSERVING PRAIRIE PONDS FOR SWALLOWS: TREE SWALLOW (TACHYCINETA BICOLOR) FORAGING AND NESTLING DIET QUALITY IN PRAIRIE AGROECOSYSTEMS. [Internet] [Thesis]. University of Saskatchewan; 2019. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/12471.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Elgin AS1. CONSERVING PRAIRIE PONDS FOR SWALLOWS: TREE SWALLOW (TACHYCINETA BICOLOR) FORAGING AND NESTLING DIET QUALITY IN PRAIRIE AGROECOSYSTEMS. [Thesis]. University of Saskatchewan; 2019. Available from: http://hdl.handle.net/10388/12471

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Bairos-Novak, Kevin R. Prey responses to disturbance cues: Effects of familiarity, kinship, and past experience with risk.

Degree: 2018, University of Saskatchewan

URL: http://hdl.handle.net/10388/8535

► Prey can acquire information about predators by eavesdropping on conspecific cues, but these cues are not always reliable. In aquatic systems, disturbance cues are pulses… (more)

▼ Prey can acquire information about predators by eavesdropping on conspecific cues, but these cues are not always reliable. In aquatic systems, disturbance cues are pulses of urea or ammonia that are often released by prey while fleeing a predator; nearby individuals typically display antipredator responses after detecting these cues. Despite the importance of disturbance cues to aquatic prey survival, they remain largely understudied in terms of their function and evolution. Here, I sought to test whether disturbance cues might function as an antipredator signal. Using a series of experiments, I assessed how familiarity and relatedness with individuals releasing the cues affects the antipredator response of the receiver, and whether background risk levels for the cue releaser and receiver play a role in the response exhibited by the receiver. If prey rely more on disturbance cues from familiar, related, or high predation risk background conspecifics, then I expect to see a heightened fright response to these cues. To test this, I raised wood frog (Lithobates sylvaticus) egg clutches and obtained disturbance cues from groups of tadpoles by simulating a predator chase. Counter to expectation, tadpoles exposed to disturbance cues from unfamiliar individuals displayed a fright response, whereas disturbance cues from familiar individuals were ignored, possibly because these cues became unreliable after being detected repeatedly in the absence of a true threat. Tadpoles responded similarly to the disturbance cues of related and unrelated individuals, suggesting that related individuals did not provide more reliable information. When manipulating background predation risk, high-risk receivers but not low-risk receivers responded to disturbance cues from low-risk donors, suggesting a lower response threshold in high risk prey. Disturbance cues from high-risk donors also elicited more of a fright response in both high- and low-risk receivers. This suggests that high risk prey release more, or more potent disturbance cues. Taken together, these experiments provide strong evidence that tadpoles detect variation in disturbance cues and may be capable of modulating their disturbance cues as antipredator signals. These findings are of important consideration for conservationists studying how Allee effects manifest in threatened aquatic species such as anuran tadpoles. Advisors/Committee Members: Ferrari, Maud CO, Chivers, Douglas P, Clark, Robert G, Lane, Jeffrey E, Moya, Diego, Wei, Yangdou.

Subjects/Keywords: disturbance cues; antipredator; aquatic cue; signal; wood frog; tadpole; familiarity; kinship; background risk; predation risk

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APA (6^th Edition):

Bairos-Novak, K. R. (2018). Prey responses to disturbance cues: Effects of familiarity, kinship, and past experience with risk. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/8535

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bairos-Novak, Kevin R. “Prey responses to disturbance cues: Effects of familiarity, kinship, and past experience with risk.” 2018. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/8535.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bairos-Novak, Kevin R. “Prey responses to disturbance cues: Effects of familiarity, kinship, and past experience with risk.” 2018. Web. 18 Jan 2021.

Vancouver:

Bairos-Novak KR. Prey responses to disturbance cues: Effects of familiarity, kinship, and past experience with risk. [Internet] [Thesis]. University of Saskatchewan; 2018. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/8535.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bairos-Novak KR. Prey responses to disturbance cues: Effects of familiarity, kinship, and past experience with risk. [Thesis]. University of Saskatchewan; 2018. Available from: http://hdl.handle.net/10388/8535

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

4. Wheeler, Amy Loy. Habitat Selection by Parturient and Post-parturient Adult Female Moose (Alces alces) on the Canadian Prairies.

Degree: 2020, University of Saskatchewan

URL: http://hdl.handle.net/10388/12836

► The expansion of moose into the agricultural landscape of Saskatchewan (i.e., farmland moose) has increased human-wildlife conflicts, raising questions about how to best manage them.… (more)

▼ The expansion of moose into the agricultural landscape of Saskatchewan (i.e., farmland moose) has increased human-wildlife conflicts, raising questions about how to best manage them. To support decision making, I initiated a study on farmland moose reproductive success and habitat selection following parturition (i.e., birth of calves). In 2013 and 2014, adult female moose were captured between Saskatoon and Chamberlain, SK and fitted with Global Positioning System collars. Daily movement rates and clustering of locations were used to determine the date and location of parturition for 27 adult female moose from 2013 to 2015. The mean date of parturition was May 21. Moose were surveyed using Very High Frequency radio telemetry in June and September each year to visually determine the presence and number of calves. Of the pregnant females observed during calf surveys with 1 or 2 calves, twinning rates were 67% (n = 6/9) in June 2013 and 46% (n = 5/11) in June 2014. Habitat selection ratios indicated that wetland and riparian habitat, trees and shrubs, and cropland were selected the most strongly by female moose as parturition habitat, while pastures and forages, developed and native grassland habitat were avoided. Female moose selected parturition sites further away from roads. A resource selection function model was developed to quantify habitat selection by 15 female moose with young during the first 20 days post-parturition. During this period, adult female moose with young most strongly selected for wetland and riparian areas (β [95% CI] = 0.716 [0.485, 0.946]) and native grassland (β [95% CI] = 0.457 [0.329, 0.585]) and against oilseeds (β [95% CI] = –0.252 [–0.400, –0.103]). Predictive success of the top-ranked model, estimated from k-fold cross validation, was rs = 0.993 (SE = 0.001). The resource selection function indicates that only 10% of the area within the home ranges of parturient females is considered highly selected habitat with high probability of moose use, while 48% of the area has a low probability of use. These results demonstrate the importance of wetland habitat within cropland to female moose, during and shortly after giving birth. Advisors/Committee Members: Brook, Ryan K, Buchanan, Fiona C, Hogan, Natacha S, Clark, Robert G, McCance, Erin C.

Subjects/Keywords: moose; parturition; habitat selection; resource selection

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wheeler, A. L. (2020). Habitat Selection by Parturient and Post-parturient Adult Female Moose (Alces alces) on the Canadian Prairies. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12836

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wheeler, Amy Loy. “Habitat Selection by Parturient and Post-parturient Adult Female Moose (Alces alces) on the Canadian Prairies.” 2020. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/12836.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wheeler, Amy Loy. “Habitat Selection by Parturient and Post-parturient Adult Female Moose (Alces alces) on the Canadian Prairies.” 2020. Web. 18 Jan 2021.

Vancouver:

Wheeler AL. Habitat Selection by Parturient and Post-parturient Adult Female Moose (Alces alces) on the Canadian Prairies. [Internet] [Thesis]. University of Saskatchewan; 2020. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/12836.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wheeler AL. Habitat Selection by Parturient and Post-parturient Adult Female Moose (Alces alces) on the Canadian Prairies. [Thesis]. University of Saskatchewan; 2020. Available from: http://hdl.handle.net/10388/12836

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

5. Evelsizer, Daniel Dean. Management of avian botulism and survival of molting mallards.

Degree: 2002, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-04062010-141753

► Avian botulism outbreaks are perpetuated by proliferation of toxin producing Clostridium botulinum in bird carcasses and consumption of maggots containing toxin by healthy birds. Removal… (more)

…Afton 1998). Methods were approved by the University of Saskatchewan's Committee on…

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APA (6^th Edition):

Evelsizer, D. D. (2002). Management of avian botulism and survival of molting mallards. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-04062010-141753

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Evelsizer, Daniel Dean. “Management of avian botulism and survival of molting mallards.” 2002. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-04062010-141753.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Evelsizer, Daniel Dean. “Management of avian botulism and survival of molting mallards.” 2002. Web. 18 Jan 2021.

Vancouver:

Evelsizer DD. Management of avian botulism and survival of molting mallards. [Internet] [Thesis]. University of Saskatchewan; 2002. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-04062010-141753.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Evelsizer DD. Management of avian botulism and survival of molting mallards. [Thesis]. University of Saskatchewan; 2002. Available from: http://hdl.handle.net/10388/etd-04062010-141753

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

6. DÃ©sy, Julie. Fate and effects of triallate in a prairie wetland.

Degree: 1996, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-06062012-104448

► Extensive use of pesticides in the Canadian prairies, where cropland is interspersed with wetlands, increases the potential for contamination of aquatic ecosystems. Triallate is a… (more)

▼ Extensive use of pesticides in the Canadian prairies, where cropland is interspersed with wetlands, increases the potential for contamination of aquatic ecosystems. Triallate is a widely used herbicide for the control of wild oats and it is frequently detected in aquatic systems. Because triallate is toxic to aquatic organisms and has the potential to persist in sediment, its impact on natural systems needs to be evaluated. The purpose of this research was to determine the fate of triallate in wetlands and its effect on selected aquatic organisms representing different trophic levels. Four littoral enclosures were built in a prairie pond; each was divided in half creating paired treatment and control cells. Triallate was applied at a concentration of 250 Âµg/L, representing a worst-case contamination by runoff. Time-specific concentrations of triallate in water, sediment and biota were measured. Triallate disappeared quickly from the water and partitioned to the sediment. Volatilization and uptake by organisms may have contributed to decreasing water concentrations. Levels in water decreased sharply in the first 3 days following application coupled with rising sediment concentrations. Levels in amphipods and aquatic plants also increased. Effects of triallate were evaluated for phytoplankton, periphyton, zooplankton (Daphnia pulex) and amphipods (Hyalella azteca). Biomass of phytoplankton and periphyton was not affected by triallate. Daphnia pulex and Hyalella azteca suffered reduced body size and reproduction. However, some of the results were inconsistent among enclosures. Microcosm and laboratory experiments were performed to complement the field study and demonstrated the toxicity of triallate to phytoplankton and D. pulex. Sublethal effects of triallate were manifested by reduced body size and reproduction in D. pulex exposed to 125 Âµg/L of triallate. These findings agree with results obtained in the field study. The present interim guideline (0.24 Âµg/L) for the protection of aquatic life appears to be adequate. In natural systems, triallate binds to dissolved and particulate organic matter and partitions quickly to sediment, reducing the amount present in solution and therefore the exposure to aquatic organisms. However, triallate persists in sediment for a longer time period and the toxicity of triallate associated with sediment has not been evaluated. Advisors/Committee Members: Clark, Robert G., Blakey, B.R., Forsyth, D.J., Sisodia, C.S..

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

DÃ©sy, J. (1996). Fate and effects of triallate in a prairie wetland. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-06062012-104448

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

DÃ©sy, Julie. “Fate and effects of triallate in a prairie wetland.” 1996. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-06062012-104448.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

DÃ©sy, Julie. “Fate and effects of triallate in a prairie wetland.” 1996. Web. 18 Jan 2021.

Vancouver:

DÃ©sy J. Fate and effects of triallate in a prairie wetland. [Internet] [Thesis]. University of Saskatchewan; 1996. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-06062012-104448.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

DÃ©sy J. Fate and effects of triallate in a prairie wetland. [Thesis]. University of Saskatchewan; 1996. Available from: http://hdl.handle.net/10388/etd-06062012-104448

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

7. Sheppard, Jennifer. Habitat selection trade-offs, male quality and reproductive performance of female mallards.

Degree: 2013, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2013-09-1231

► Conservation programs for breeding ducks in North America are typically designed to enhance nest success by establishing or restoring attractive perennial nesting cover or promoting… (more)

▼ Conservation programs for breeding ducks in North America are typically designed to enhance nest success by establishing or restoring attractive perennial nesting cover or promoting favourable agricultural practices. Thus, a central objective is to attract ducks to habitats where females have higher survival and reproductive rates, primarily greater nest success. Using data collected from 1993 – 2000, I investigated hypotheses proposed to explain inconsistent patterns of habitat selection detected during nesting and brood–rearing stages in free-ranging mallards (Anas platyrhynchos) throughout the Canadian Prairie Parklands. By simultaneously considering indices of body condition and size of male and female mallards and plumage score of males, I also evaluated the role of male quality in reproductive investment and patterns of breeding success of females. In general, wild mallards mated assortatively by body condition but not body size. Yearling females nested earlier and had higher nest survival when mated to males with better plumage quality. When paired with larger-bodied males, yearling females renested more often, whereas nest and brood survival increased among older females. I characterized the habitat composition of 100 and 500 m radius buffers surrounding nest sites and related habitat features to survival of nests, broods and females. Habitat selection trade-offs were detected among perennial habitats and planted cover, such that nest survival increased in these habitats whereas duckling survival decreased. Furthermore, at large spatial scales, nest survival decreased in areas with greater amounts of cropland whereas duckling survival increased. Survival rates of females increased with greater amounts of seasonal wetlands, but nest survival decreased in such areas. Semi-permanent wetlands were associated with decreased nest survival at larger spatial scales, but associated with higher nest success at finer scales. Benefits of increasing perennial and planted cover habitats to increase nest survival could be partly offset by costs in terms of lower duckling survival, whereas opposite patterns existed in areas of abundant seasonal. The restoration of seasonal wetlands in perennial habitats could offset these trade-offs but net impacts of habitat selection and survival trade-offs on annual reproductive success must first be evaluated. Advisors/Committee Members: Clark, Robert G., Howerter, David W., Wiebe, Karen, Bell, Scott.

Subjects/Keywords: mallard; Anas platyrhynchos; habitat selection; reproductive investment; male quality

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APA (6^th Edition):

Sheppard, J. (2013). Habitat selection trade-offs, male quality and reproductive performance of female mallards. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2013-09-1231

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sheppard, Jennifer. “Habitat selection trade-offs, male quality and reproductive performance of female mallards.” 2013. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/ETD-2013-09-1231.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sheppard, Jennifer. “Habitat selection trade-offs, male quality and reproductive performance of female mallards.” 2013. Web. 18 Jan 2021.

Vancouver:

Sheppard J. Habitat selection trade-offs, male quality and reproductive performance of female mallards. [Internet] [Thesis]. University of Saskatchewan; 2013. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/ETD-2013-09-1231.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sheppard J. Habitat selection trade-offs, male quality and reproductive performance of female mallards. [Thesis]. University of Saskatchewan; 2013. Available from: http://hdl.handle.net/10388/ETD-2013-09-1231

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

8. Gloutney, Mark Louis. Nest-site selection, energetics of reproduction and comparative behaviour of mallard (anas platyrhynchos) and blue-winged teal (A. discors).

Degree: 1996, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-10212004-000134

► An organism's reproductive success may be affected by choice of breeding habitats and subsequent investment in offspring. Nest microclimate may profoundly influence energetic costs of… (more)

▼ An organism's reproductive success may be affected by choice of breeding habitats and subsequent investment in offspring. Nest microclimate may profoundly influence energetic costs of incubation or embryonic survival, but few studies have evaluated whether birds select nest-sites based on microclimate. Likewise, increased investment of nutrients in eggs may have costs in terms of future survival and reproduction. These ideas have received only limited testing, particularly behavioural and physiological responses to clutch size variation of precocial birds. Therefore, I evaluated whether: (1) ducks select nest-sites for thermal features; and, (2) incubation behaviours, incubation periods, or energetic costs of incubation are related to clutch size. Blue-winged teal ( A. discors; hereafter teal) nested most often in grass or short shrub habitats, while mallard (Anas platyrhynchos) nested in all habitats. Within nesting habitats, microclimate followed a gradient from hot and sunny in grass-dominated sites to cool and shaded sites in aspen (Populus spp.) groves. I measured microclimatic conditions at mallard and teal nests and randomly located nonnest sites, to evaluate thermal consequences of nest-site selection. Duck nests received on average less solar insolation than nonnest sites, producing more moderate thermal conditions than at nonnest sites. When mallard and teal nests were concurrently monitored, teal selected warmer nest-sites than mallards. Thus, teal may choose warmer nests to offset costs of incubation, a hypothesis which has not been tested. Apart from egg formation costs, processes occurring during incubation may also limit clutch size of precocial birds. I tested if incubation periods were positively correlated with clutch size and found that incubation periods of captive mallards and wild teal, but not wild mallards, were longer for females incubating clutches enlarged by 50%. Incubating females may respond to increased energetic costs of incubation by: (1) losing more mass, (2) decreasing nest attendance, or (3) some combination of both. Mass loss and mass at hatch were unrelated to clutch enlargement, however, mass loss was positively correlated with mass at the start of incubation. While controlling for effects of weather, I found no change in incubation behaviours of mallards incubating enlarged clutches, but, teal increased overall recess frequency. Finally, I evaluated effects of clutch enlargement on incubation strategies, representing an integration of behaviour and body mass dynamics. When controlling for weather and body mass dynamics, clutch enlargement produced significant, yet subtle changes in incubation behaviours. Mallards took slightly shorter recesses, but maintained constancy, whereas teal increased recess frequency and decreased nest attendance. Energetic costs of incubation are controversial. I tested if incubation metabolic rates (IMR) were greater than resting metabolic rate (RMR). Incubation caused an increase in metabolic rate by mallard and red junglefowl (Gallus gallus… Advisors/Committee Members: Clark, Robert G..

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APA (6^th Edition):

Gloutney, M. L. (1996). Nest-site selection, energetics of reproduction and comparative behaviour of mallard (anas platyrhynchos) and blue-winged teal (A. discors). (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-10212004-000134

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gloutney, Mark Louis. “Nest-site selection, energetics of reproduction and comparative behaviour of mallard (anas platyrhynchos) and blue-winged teal (A. discors).” 1996. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-10212004-000134.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gloutney, Mark Louis. “Nest-site selection, energetics of reproduction and comparative behaviour of mallard (anas platyrhynchos) and blue-winged teal (A. discors).” 1996. Web. 18 Jan 2021.

Vancouver:

Gloutney ML. Nest-site selection, energetics of reproduction and comparative behaviour of mallard (anas platyrhynchos) and blue-winged teal (A. discors). [Internet] [Thesis]. University of Saskatchewan; 1996. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-10212004-000134.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gloutney ML. Nest-site selection, energetics of reproduction and comparative behaviour of mallard (anas platyrhynchos) and blue-winged teal (A. discors). [Thesis]. University of Saskatchewan; 1996. Available from: http://hdl.handle.net/10388/etd-10212004-000134

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

9. Rangen, Sheila Anne. Boreal forest songbird diversity and reproductive success : roles of vegetation, predators, and competitors.

Degree: 2000, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-10212004-002350

► The hypothesis that predators diversify songbird communities, by preying more heavily on individuals and species with greatest similarity in nest site use, was evaluated using… (more)

▼ The hypothesis that predators diversify songbird communities, by preying more heavily on individuals and species with greatest similarity in nest site use, was evaluated using field studies in boreal forests of Alberta and Saskatchewan and artificial nest experiments in Alberta. Positive relationships between predator diversity or abundance and diversity, of birds were detected, after controlling effects of vegetation. Limited competition may have also contributed to patterns of bird diversity because there were more positive than negative associations between ecologically similar congeners. Predator responses to artificial songbird nests that varied in nest-site placement, vegetation features and nest spacing patterns were also examined. Predators were expected to destroy nests characterized by similar vegetation features or nest types. Variability among nest sites was achieved by deploying nests throughout a gradient of vegetation and by deploying nests to simulate two- and three-species assemblages. However, predation did not increase as variance in vegetation surrounding nest sites decreased across plots nor did variance in vegetation surrounding successful nests increase among plots as predation level increased. The addition of another species' nest type to assemblages did riot result in lower predation rates, nor did predators destroy more clumped than randomly distributed nests. Data from these and other artificial nest experiments were used to identify habitat attributes associated with successful nests versus those destroyed by specific predators. Successful nests and those visited by mice tended to be ground nests well-concealed by dense Shrubs. Squirrels and birds usually visited above-ground nests at sites with few shrubs and high tree densities. Reliability of patterns of songbird productivity was tested using artificial nests (visual and olfactory cues) and indices of reproductive success in mixedwood forest of Alberta. Avian predators did riot discriminate between wicker nests dipped in mud and wicker nests covered by, a camouflage fabric, whereas mammalian predators showed a weak tendency to depredate camouflaged nests. Nests containing plasticine eggs in field experiments and egg assortments containing plasticine eggs in laboratory experiments with captive deer mice (Peromyscus maniculatus) were depredated more than those only containing finch and quail eggs. Young and old forest stands were used to compare differences in reproductive effort and success, using songbird behavior and number of fledglings. Some species differed in density (17%), indices of reproductive behavior (33%), and number of fledglings observed (13%) between stand-ages. Using behavioral indices or fledgling numbers to estimate nesting success in forested habitats did not appear feasible. Also, a presumed positive relationship between indices of reproductive success density were obtained for only 40-45% of species. Overall, results were consistent, in part, with evidence that mechanisms other than competition or… Advisors/Committee Members: Clark, Robert G..

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rangen, S. A. (2000). Boreal forest songbird diversity and reproductive success : roles of vegetation, predators, and competitors. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-10212004-002350

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Rangen, Sheila Anne. “Boreal forest songbird diversity and reproductive success : roles of vegetation, predators, and competitors.” 2000. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-10212004-002350.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Rangen, Sheila Anne. “Boreal forest songbird diversity and reproductive success : roles of vegetation, predators, and competitors.” 2000. Web. 18 Jan 2021.

Vancouver:

Rangen SA. Boreal forest songbird diversity and reproductive success : roles of vegetation, predators, and competitors. [Internet] [Thesis]. University of Saskatchewan; 2000. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-10212004-002350.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rangen SA. Boreal forest songbird diversity and reproductive success : roles of vegetation, predators, and competitors. [Thesis]. University of Saskatchewan; 2000. Available from: http://hdl.handle.net/10388/etd-10212004-002350

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

10. Ross, Megan V 1992-. Ecological factors affecting midcontinent light goose recruitment.

Degree: 2016, University of Saskatchewan

URL: http://hdl.handle.net/10388/7644

► A full understanding of population dynamics requires knowledge about the relative contributions of both adult survival and recruitment to population growth rate. Avian life cycles… (more)

▼ A full understanding of population dynamics requires knowledge about the relative contributions of both adult survival and recruitment to population growth rate. Avian life cycles consist of a number of reproductive stages leading to recruitment, each of which is highly susceptible to annual variability in environmental conditions. The purpose of my research was to identify key ecological factors associated with a long-term decline in the per capita gosling production of Ross’s geese (Chen rossii) and lesser snow geese (Chen caerulescens caerulescens) using historical data collected from 1992-2014 at Karrak Lake, Nunavut. I evaluated effects of (i) nutritional deficiencies of pre-breeding female Ross’s geese and lesser snow geese stemming from density-dependence following large increases in nesting population size and (ii) phenological mismatch between peak gosling hatch and peak forage quality, inferred from measurements of NDVI on brood-rearing areas. Annual gosling production (i.e., proportional composition of young during brood-rearing) was reduced for both species when the mass of nutrient reserves for pre-breeding females arriving to nest were lighter. Mismatch between peak gosling hatch and peak forage quality was also related to decreases in gosling production, while delays in nest initiation negatively affected clutch size and nest success (i.e., ≥ 1 egg hatched). Vegetation phenology was significantly earlier in years with warmer spring (i.e., 25 May – 30 June) surface air temperatures. Additionally, increased mismatch over the course of the 23-year study period apparently resulted from advancing vegetation phenology without a contemporaneous advance in goose breeding phenology. I did not find evidence of a direct effect of annual nesting population size on colony gosling production. Given an absence of information on the pre-fledging stage of the life cycle for geese originating from Karrak Lake, I studied the effect of conditions experienced during early life on the growth and survival of goslings. Time constraints due to strong seasonality at arctic-nesting grounds highlight the importance of foraging conditions (i.e., quality, quantity, availability) for offspring during brood-rearing. I found that an increase in the number of nesting geese was associated with a reduction in gosling survival for both Ross’s geese and snow geese. There was weak evidence that snow goose gosling body size was negatively related to breeding population size at the colony, while no effect was detected for Ross’s geese. Increasing mismatch between the seasonal peak in vegetation quality and timing of hatch was negatively related to both gosling size and survival probability; suggestive of nutritional stress. My results lend support to the notion that both global (i.e., climate change) and local (i.e., foraging/habitat conditions) phenomena may result in reduced offspring production and success, and alludes to the possibility of an eventual decline in recruitment into the breeding cohort. Advisors/Committee Members: Morrissey, Christy A, Clark, Robert G, Wei, Yangdou D, Clark, Douglas A.

Subjects/Keywords: arctic; breeding phenology; climate change; density dependence; geese; nutrient reserves; mismatch; gosling survival

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APA (6^th Edition):

Ross, M. V. 1. (2016). Ecological factors affecting midcontinent light goose recruitment. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/7644

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ross, Megan V 1992-. “Ecological factors affecting midcontinent light goose recruitment.” 2016. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/7644.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ross, Megan V 1992-. “Ecological factors affecting midcontinent light goose recruitment.” 2016. Web. 18 Jan 2021.

Vancouver:

Ross MV1. Ecological factors affecting midcontinent light goose recruitment. [Internet] [Thesis]. University of Saskatchewan; 2016. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/7644.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ross MV1. Ecological factors affecting midcontinent light goose recruitment. [Thesis]. University of Saskatchewan; 2016. Available from: http://hdl.handle.net/10388/7644

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

11. Devries, James. Fitness consequences of avian habitat selection in dynamic landscapes : multi-scale evaluations in northern pintails.

Degree: 2014, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2014-10-1788

► According to theory, habitat selection by organisms should reflect the associated probability of survival or reproductive success. Understanding habitat selection, at multiple scales, is of… (more)

▼ According to theory, habitat selection by organisms should reflect the associated probability of survival or reproductive success. Understanding habitat selection, at multiple scales, is of interest not only from a theoretical perspective, but from an applied perspective for species conservation. Northern pintails (Anas acuta) are migratory, temperate-nesting birds that breed in greatest concentrations in the prairies of North America. Declining populations suggest that habitat loss and changing land use may have decoupled formerly reliable fitness cues from selection of suitable nest habitat. I used data from 62 waterfowl nesting study sites in prairie Canada (1997–2009), to examine whether nest survival, a primary fitness metric, at nest and habitat patch scales, was predictive of habitat selection at corresponding scales. In addition, I used systematic long-term annual pintail population monitoring data (1961–2009), and recruitment indices (juvenile:adult female ratio) from hunter harvest, to examine adaptive habitat selection among landscapes within the Prairie Pothole Region (PPR). The influences of breeding population density and landscape composition were examined at all scales. At nest and patch scales, pintail nest survival varied with nest initiation date, nest habitat, pair density, and landscape composition. Nest habitat preference reflected patterns in nest survival suggesting nest habitat preference is adaptive. Preference was generally low for habitats with low nest survival (e.g., spring-seeded cropland) and high for habitats with high nest survival (e.g., idle grassland). Differences in preference among habitats weakened at high breeding density and in landscapes with more grassland. Population-level recruitment tended to be greater when pintails settled in landscapes that were wetter than normal, contained more grassland, and were moderately variable in local elevation. Pintails were strongly associated with wetter than normal landscapes but shifted into cropland-dominated landscapes and flatter landscapes when populations were high. My results indicated that pintails express adaptive habitat associations with density-dependence acting through buffer mechanisms. Finally, I use the results of the above analyses to, 1) model and map the estimated long-term average spatial abundance of pintail pairs across the PPR as a function of landscape-level covariates, and 2) construct a deterministic model predicting pintail productivity given habitat and landscape attributes. These models allow conservation efforts to be targeted to affect the most birds, and they allow estimation of the demographic response to conservation actions. Advisors/Committee Members: Clark, Robert G., Wiebe, Karen L., McLoughlin, Philip D., Belcher, Ken W., Eadie, John M..

Subjects/Keywords: northern pintail; habitat selection; demographic models; conservation planning

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APA (6^th Edition):

Devries, J. (2014). Fitness consequences of avian habitat selection in dynamic landscapes : multi-scale evaluations in northern pintails. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2014-10-1788

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Devries, James. “Fitness consequences of avian habitat selection in dynamic landscapes : multi-scale evaluations in northern pintails.” 2014. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/ETD-2014-10-1788.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Devries, James. “Fitness consequences of avian habitat selection in dynamic landscapes : multi-scale evaluations in northern pintails.” 2014. Web. 18 Jan 2021.

Vancouver:

Devries J. Fitness consequences of avian habitat selection in dynamic landscapes : multi-scale evaluations in northern pintails. [Internet] [Thesis]. University of Saskatchewan; 2014. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/ETD-2014-10-1788.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Devries J. Fitness consequences of avian habitat selection in dynamic landscapes : multi-scale evaluations in northern pintails. [Thesis]. University of Saskatchewan; 2014. Available from: http://hdl.handle.net/10388/ETD-2014-10-1788

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

12. Routhier, Daniel. Spatiotemporal Variation in Occupancy and Productivity of Grebes in Prairie Canada: Estimation and Conservation Applications.

Degree: 2012, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2012-09-674

► Wetlands of the Prairie Pothole Region (PPR) provide important breeding habitat for greater than 30 species of waterbirds. Approximately 70% of PPR wetlands have been… (more)

▼ Wetlands of the Prairie Pothole Region (PPR) provide important breeding habitat for greater than 30 species of waterbirds. Approximately 70% of PPR wetlands have been lost since European settlement and remaining wetlands are subjected to frequent degradation, primarily due to agricultural activities. Horned grebes (Podiceps auritus) are experiencing long-term population declines and are listed as a species of Special Concern in Canada. Because there is virtually no information on the status and trends of pied-billed grebes (Podilymbus podicep) this species is also of considerable conservation concern. Grebes are recorded on the Waterfowl Breeding Population and Habitat Surveys (WBPHS) conducted annually in May by the Canadian Wildlife Service; however, how accurately these counts reflect actual abundance has been unknown. Using a repeated counts method in 2010 and 2011, estimates of detection probabilities averaged 0.48 and 0.18 for horned and pied-billed grebes, respectively. These results suggest that WBPHS ground surveys may be used as an efficient and effective management tool for monitoring horned grebe abundances. However, low detection rates for pied-billed grebes lend little support for including the species in future monitoring efforts using the WBPHS. I recommend that the Canadian Wildlife Service consider implementing standardized ground survey methods to facilitate annual monitoring of horned grebe abundances. Marshbird research has focused primarily on breeding habitat use or selection but has seldom examined how productivity is related to wetland characteristics. Understanding processes that affect distribution patterns and productivity of grebes could provide insights into actions needed to achieve conservation goals. Therefore, occupancy of wetlands by breeding and brood-rearing horned and pied-billed grebes was evaluated on 6-7 study sites (5.8-11.6 km2) in south-central Saskatchewan, 2010 and 2011, and related to wetland and upland habitat features. Wetland occupancy by grebes was influenced by interspecific competition as well as local and landscape-level wetland features. Horned and pied-billed grebes rarely co-occurred on smaller (≤4 ha) semi-permanent and permanent wetlands. At the wetland level, horned grebe occupancy and productivity were highly correlated with the amount of emergent vegetation, whereas wetland area alone was a better predictor of adult pied-billed grebe occupancy and productivity. At a landscape level, the number of semi-permanent, permanent, and artificial wetlands on each study site was an important predictor of breeding and brood-rearing wetland occupancy probability for horned grebes in 2010 and for pied-billed grebes in both years. However, breeding horned grebe occupancy probability and productivity were higher in low wetland density landscapes in 2011. Horned grebes may be opportunistic, exploiting more of the available wetland habitats in low wetland density landscapes during years of above-average water conditions. Conservation initiatives for grebes should… Advisors/Committee Members: Clark, Robert G., Dufour, Kevin W., Alisauskas, Ray T., Morrissey, Christy A..

Subjects/Keywords: abundance; detection probability; horned grebe; pied-billed grebe; occupancy; Podiceps auritus; Podylimbus podiceps

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APA (6^th Edition):

Routhier, D. (2012). Spatiotemporal Variation in Occupancy and Productivity of Grebes in Prairie Canada: Estimation and Conservation Applications. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2012-09-674

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Routhier, Daniel. “Spatiotemporal Variation in Occupancy and Productivity of Grebes in Prairie Canada: Estimation and Conservation Applications.” 2012. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/ETD-2012-09-674.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Routhier, Daniel. “Spatiotemporal Variation in Occupancy and Productivity of Grebes in Prairie Canada: Estimation and Conservation Applications.” 2012. Web. 18 Jan 2021.

Vancouver:

Routhier D. Spatiotemporal Variation in Occupancy and Productivity of Grebes in Prairie Canada: Estimation and Conservation Applications. [Internet] [Thesis]. University of Saskatchewan; 2012. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/ETD-2012-09-674.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Routhier D. Spatiotemporal Variation in Occupancy and Productivity of Grebes in Prairie Canada: Estimation and Conservation Applications. [Thesis]. University of Saskatchewan; 2012. Available from: http://hdl.handle.net/10388/ETD-2012-09-674

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

13. Yang, June. Impacts of habitat and landscape characteristics on reproductive ecology of female lesser scaup (Aythya affinis) in the boreal forests of Alberta.

Degree: 2012, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2012-12-875

► The lesser scaup (Aythya affinis, henceforth scaup) population decreased during the 1980s and has remained below conservation objectives. With two-thirds of the breeding population nesting… (more)

▼ The lesser scaup (Aythya affinis, henceforth scaup) population decreased during the 1980s and has remained below conservation objectives. With two-thirds of the breeding population nesting in boreal forests, it is imperative to understand how changes in habitat features and landscape changes could negatively impact breeding scaup; this information could also help to guide waterfowl conservation and management programs. It has been hypothesized that landscape modifications, such as agricultural and oil exploitation activities, could adversely affect scaup reproductive performance. Female scaup were collected by shooting in the boreal forest fringe of central Alberta during within the first two weeks of June 2008 and 2009, corresponding to the early laying period. Collection location was determined using a hand-held GPS device and body mass (BM, g) was recorded immediately. When scaup carcasses were dissected, ovaries were removed and weighed. Rapidly growing follicles (RGF) and oviductal follicles (OF) were subjected to radioimmunoassay to quantify amount of ovarian corticosterone (OCORT) deposited into follicles. Nest initiation date (NID) was determined by counting and subtracting the number of postovulatory follicles (POF) from collection date. Natural landscape features and habitat disturbances within 100 m, 250 m, 500 m, 1500 m, and 5000 m buffers of each scaup collection location were quantified, and then normalized using z-score transformation. General linear modeling was applied to BM, OCORT and NID across each of the five buffer sizes using a priori candidate models. Natural landscape and habitat disturbance parameters were model-averaged to obtain 85% confidence intervals to determine which habitat features best predicted BM, NID, and OCORT. Model-averaging revealed that the amount of natural water body habitats were negatively correlated to scaup OCORT at the 100 m and 500 m buffer zones, and negatively correlated to scaup BM at 1500 m and 5000 m buffer zones. A combination of natural water bodies (BOGSFENS, SWAMP, WATER, and WETLAND) were negatively correlated to NID across all buffer sizes tested, AGRIC disturbance was positively correlated to NID at the 100 m and 1500 m buffer zones, WELLS were negatively correlated to NID at the 1500 m buffer zone, while TRANSPORT showed varied responses at the 1500 m and 5000 m buffer zones. Post-hoc exploratory analyses were conducted to assess whether variation in OCORT, BM, and NID was related to habitat features operating at more than one spatial scale. This analysis revealed models incorporating more than one spatial scale were competitive when compared to the original a priori model sets at the 250 m buffer zone, with post-hoc models performing better than a priori models. This study highlights the need for a holistic approach to conservation management, considering not only local habitat characteristics and disturbances in the immediate vicinity of breeding waterfowl, but extending beyond and incorporating regional landscape attributes. Advisors/Committee Members: Machin, Karen L., Clark, Robert G., Cattet, Marc R., Muir, Gillian D..

Subjects/Keywords: lesser scaup; landscape; metabolomics; reproduction

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APA (6^th Edition):

Yang, J. (2012). Impacts of habitat and landscape characteristics on reproductive ecology of female lesser scaup (Aythya affinis) in the boreal forests of Alberta. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2012-12-875

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Yang, June. “Impacts of habitat and landscape characteristics on reproductive ecology of female lesser scaup (Aythya affinis) in the boreal forests of Alberta.” 2012. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/ETD-2012-12-875.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Yang, June. “Impacts of habitat and landscape characteristics on reproductive ecology of female lesser scaup (Aythya affinis) in the boreal forests of Alberta.” 2012. Web. 18 Jan 2021.

Vancouver:

Yang J. Impacts of habitat and landscape characteristics on reproductive ecology of female lesser scaup (Aythya affinis) in the boreal forests of Alberta. [Internet] [Thesis]. University of Saskatchewan; 2012. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/ETD-2012-12-875.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Yang J. Impacts of habitat and landscape characteristics on reproductive ecology of female lesser scaup (Aythya affinis) in the boreal forests of Alberta. [Thesis]. University of Saskatchewan; 2012. Available from: http://hdl.handle.net/10388/ETD-2012-12-875

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

14. Wishingrad, Van. Behavioural ecology of foraging and predator avoidance trade-offs in Lake Sturgeon (Acipenser fulvescens).

Degree: 2014, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2014-04-1516

► I investigated Lake Sturgeon (Acipenser fulvescens) foraging and anti-predator behaviour. My goals were to understand: (1) The role of environmental change on foraging and anti-predator… (more)

▼ I investigated Lake Sturgeon (Acipenser fulvescens) foraging and anti-predator behaviour. My goals were to understand: (1) The role of environmental change on foraging and anti-predator behaviour trade-offs. (2) The relative cost/benefit trade-off between escape behaviour and cover-seeking behaviour. (3) How development of several independent morphological traits affects anti-predator behaviours. I used simulated river mesocosms to study Lake Sturgeon behavioural ecology under controlled conditions. I found: (1) Foraging intensity was significantly higher during the night than the day as well as in turbid environments versus clear environments, indicating that decreased turbidity alone, may in part drive anti-predator behaviour and constrain foraging activity. (2) In high-risk clear-water environments, Lake Sturgeon responded to danger by evoking an escape response and seeking cover in rocky microhabitats. However, in low-risk turbid environments, Lake Sturgeon responded to danger by seeking cover in rocky microhabitats, but not fleeing to a significant degree. Cover-seeking behaviour may therefore be a relatively low-cost/high-benefit anti-predator strategy. (3) Strong evidence for trait co-dependence between escape responses and body size, where larger fish were able to elicit stronger escape responses. I also found that cover-seeking behaviour exhibited a complex multi-tiered relationship, representing a mixture of trait compensation and trait co-specialization that is dependent on specific combinations of morphological traits. These findings are important because they help us understand: (1) The degree to which anti-predator behaviour can be influenced by changing environmental conditions. (2) The relative cost/benefit trade-off between two common anti-predator behaviours. (3) How behaviour and morphology interact in species with a complex anti-predator phenotype. Advisors/Committee Members: Chivers, Douglas P., Ferrari, Maud C., Clark, Robert G., Pollock, Michael S..

Subjects/Keywords: anti-predator behaviour; foraging; trade-off; optimality; predator-prey interactions; alarm cue; turbidity; morphology; crypsis; mottled; scutes; armour; spines; cover-seeking; habitat selection; escape response; escape behaviour; lake sturgeon; defensive morphology

…of Douglas P Chivers and Maud CO Ferrari (University of Saskatchewan). Chapter 4… …Douglas P Chivers (University of Saskatchewan). 6 CHAPTER 2: RISK IN A CHANGING… …of Saskatchewan). Chapter 3 has been submitted to Ethology, under the joint authorship… …joint authorship of Annessa B Musgrove, Douglas P Chivers and Maud CO Ferrari (University…

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APA (6^th Edition):

Wishingrad, V. (2014). Behavioural ecology of foraging and predator avoidance trade-offs in Lake Sturgeon (Acipenser fulvescens). (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2014-04-1516

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wishingrad, Van. “Behavioural ecology of foraging and predator avoidance trade-offs in Lake Sturgeon (Acipenser fulvescens).” 2014. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/ETD-2014-04-1516.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wishingrad, Van. “Behavioural ecology of foraging and predator avoidance trade-offs in Lake Sturgeon (Acipenser fulvescens).” 2014. Web. 18 Jan 2021.

Vancouver:

Wishingrad V. Behavioural ecology of foraging and predator avoidance trade-offs in Lake Sturgeon (Acipenser fulvescens). [Internet] [Thesis]. University of Saskatchewan; 2014. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/ETD-2014-04-1516.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wishingrad V. Behavioural ecology of foraging and predator avoidance trade-offs in Lake Sturgeon (Acipenser fulvescens). [Thesis]. University of Saskatchewan; 2014. Available from: http://hdl.handle.net/10388/ETD-2014-04-1516

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

15. Guyn, Karla Lee. Breeding ecology of northern pintails : nesting ecology, nest-site selection, nutrient reserve use and brood ecology.

Degree: 2000, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-10212004-002353

► To meet nutritional demands of egg laying, female pintails obtain nutrients from either exogenous or endogenous sources. I examined use of nutrient reserves during egg… (more)

▼ To meet nutritional demands of egg laying, female pintails obtain nutrients from either exogenous or endogenous sources. I examined use of nutrient reserves during egg formation in pintails and tested whether reserves regulated clutch size. I found that females relied heavily on fat reserves during egg laying, but found no evidence that fat, or protein, proximately limited clutch size. I tested whether nest-site selection patterns were based on vegetative features, female characteristics, or whether site selection was based on nest microclimate. Pintail nests were characterized by less short grass, more shrub cover and were more frequently found in depression than random sites; unsuccessful nests were closer to shrubs than successful ones. The microclimate of nests differed from that of random sites, nests being about 2°C cooler on average than random sites during daylight hours. Furthermore, 30-minute mean temperatures exceeded the upper lethal limit for embryonic development more often at random sites than nest-sites. I evaluated variation in nesting effort and success of female pintails breeding in prairie habitats. I found no relationship between egg size and clutch size, or evidence from one year to the next of a trade-off between current and future investment in eggs. However, greater investment in initial clutches led to longer delays in laying replacement clutches the same year. Therefore, because delays in renesting are costly (late-nesting females produce fewer offspring), females must contend with a tradeoff between maximizing reproductive output in initial clutches versus risk of delayed renesting. I examined brood and duckling survival from radio-marked females and related duckling survival to maternal and environmental attributes. Duckling survival ranged from 42-65% with most duckling mortality occurring during the first 10 days post-hatch. Ducklings in relatively small broods had higher survival than ducklings from larger broods in 2 of 3 years, suggesting a further constraint on clutch size. Thus, trade-offs occurring at several stages likely set limits to clutch size in pintails, illustrating the need for a more comprehensive template in future studies of clutch size determinants in waterfowl and other species. Advisors/Committee Members: Clark, Robert G..

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APA (6^th Edition):

Guyn, K. L. (2000). Breeding ecology of northern pintails : nesting ecology, nest-site selection, nutrient reserve use and brood ecology. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-10212004-002353

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Guyn, Karla Lee. “Breeding ecology of northern pintails : nesting ecology, nest-site selection, nutrient reserve use and brood ecology.” 2000. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-10212004-002353.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Guyn, Karla Lee. “Breeding ecology of northern pintails : nesting ecology, nest-site selection, nutrient reserve use and brood ecology.” 2000. Web. 18 Jan 2021.

Vancouver:

Guyn KL. Breeding ecology of northern pintails : nesting ecology, nest-site selection, nutrient reserve use and brood ecology. [Internet] [Thesis]. University of Saskatchewan; 2000. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-10212004-002353.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Guyn KL. Breeding ecology of northern pintails : nesting ecology, nest-site selection, nutrient reserve use and brood ecology. [Thesis]. University of Saskatchewan; 2000. Available from: http://hdl.handle.net/10388/etd-10212004-002353

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

16. Michelson, Chantel. Effects of agricultural land use on tree swallow (Tachycineta bicolor) reproduction, body condition and diet.

Degree: 2015, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2015-11-2391

► Agricultural practices have intensified over the last 50 years, increasing crop production and altering the Canadian Prairie landscape by removing non-cropped habitats and wetlands. The… (more)

▼ Agricultural practices have intensified over the last 50 years, increasing crop production and altering the Canadian Prairie landscape by removing non-cropped habitats and wetlands. The productivity, trophic structure and diversity have changed through increased agrochemical inputs and reductions in yearly rotation and diversification of crop types. Most intensive agricultural practices have negative effects on invertebrate communities that can indirectly affect higher trophic organisms, such as birds. Many populations of aerial insectivorous bird species have been experiencing rapid declines in the last 30–40 years. Dependency on high abundances of aerial insects for reproduction and survival is a common link among all species of this guild. My thesis examined aerial insect abundance as a potential link between agricultural land use and the reproductive ecology, nestling body condition, and diet of an aerial insectivore species, the tree swallow (Tachycineta bicolor). My broad goal was to determine whether agriculture has deleterious effects on timing of breeding, reproductive investment and success, and nestling quality, as mediated by food supply and differences in diet. Aerial insect abundance and biomass estimates obtained from passive insect traps which capture primarily aquatic dipterans were similar between agricultural and reference sites during all stages of breeding. However, estimates derived from sweep-net sampling in terrestrial habitats in 2013 indicated higher abundances of aquatic and terrestrial Diptera at a reference site relative to agricultural sites. Multiple measures of tree swallow productivity were not related to agriculture land use but nestling body condition was significantly lower on agricultural sites. Using stable isotope analysis (delta 13C and delta 15N), I found site and age specific differences in swallow diets and isotopic niche widths but variation was not consistently related to agricultural land use. Aquatic insect prey (Diptera and Odonata) made up the majority of the diet of swallows but nestlings had a larger proportion of terrestrial Diptera which resulted in larger isotopic niche widths compared to adults. The assimilated isotopic diet of nestling and adult swallows were not strong predictors of body size, mass or condition, suggesting that site differences in the diet do not appreciably affect condition. Nestlings raised on agricultural sites had lower body condition that was not directly linked to their diet alone. This suggests other unmeasured factors related to agricultural land use may affect nestling tree swallows. This study tested responses in an aerial insectivore species to land use and potential shifts in the insect community, which may provide important information for conservation and management decisions for many species within the aerial insectivore guild. Advisors/Committee Members: Morrissey, Christy A., Clark, Robert G., Jardine, Tim, Wiebe, Karen L..

Subjects/Keywords: agricultural land use; tree swallows; reproduction; body condition; diet; stable isotopes

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APA (6^th Edition):

Michelson, C. (2015). Effects of agricultural land use on tree swallow (Tachycineta bicolor) reproduction, body condition and diet. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2015-11-2391

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Michelson, Chantel. “Effects of agricultural land use on tree swallow (Tachycineta bicolor) reproduction, body condition and diet.” 2015. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/ETD-2015-11-2391.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Michelson, Chantel. “Effects of agricultural land use on tree swallow (Tachycineta bicolor) reproduction, body condition and diet.” 2015. Web. 18 Jan 2021.

Vancouver:

Michelson C. Effects of agricultural land use on tree swallow (Tachycineta bicolor) reproduction, body condition and diet. [Internet] [Thesis]. University of Saskatchewan; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/ETD-2015-11-2391.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Michelson C. Effects of agricultural land use on tree swallow (Tachycineta bicolor) reproduction, body condition and diet. [Thesis]. University of Saskatchewan; 2015. Available from: http://hdl.handle.net/10388/ETD-2015-11-2391

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

17. Gurney, Kirsty. Reproductive ecology of temperate-nesting waterfowl : temporal and spatial patterns of investment and success in lesser scaup (Aythya affinis) (AYTHYA AFFINIS).

Degree: 2011, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2012-05-152

► Ecologists and conservation biologists alike aim to understand factors determining the abundance and distribution of free-living organisms and to pinpoint why free-ranging animal populations decline.… (more)

▼ Ecologists and conservation biologists alike aim to understand factors determining the abundance and distribution of free-living organisms and to pinpoint why free-ranging animal populations decline. My broad goals were to test ecological hypotheses related to timing of breeding and offspring survival in lesser scaup (Aythya affinis, hereafter scaup), a boreal-breeding diving duck species and to examine breeding-season explanations for why scaup populations remain below conservation goals. I demonstrated that timing of breeding and clutch size in scaup were remarkably consistent across a broad environmental gradient. Clutch initiation date was unaffected by growing season length (GSL) or latitude and was only marginally influenced by spring thaw date. Clutch size declined during the nesting season, but was unaffected by climatic variables. Although late-hatched ducklings (corrected for age and size) tended to have larger digestive systems, smaller leg muscles and lower abundances of intestinal parasites acquired through diet when compared with early-hatched individuals, timing of breeding did not independently influence duckling survival; survival declined seasonally only for ducklings raised by poor quality females. Assimilated diets of scaup ducklings were invariant with hatch date, and across a range of wetlands on two widely-separated boreal forest sites, duckling food densities did not vary throughout brood-rearing, nor did lipid content of amphipods. Taken together, my findings indicate that timing of breeding in scaup may have evolved to maximize temporal overlap between offspring and their critical food resources. Consequently, this species may be particularly sensitive to environmental changes that affect availability of prey, and I suggest that scaup conservation efforts should focus on determining how climatic factors influence invertebrate populations in key breeding areas. In addition, my study highlights the importance of maternal quality to reproductive success. Specifically, poor-quality female scaup may be unable to monopolize food resources as duckling densities increase throughout the season or may value their own survival more than that of their offspring as time constraints increase. Regardless of the exact mechanism, evaluating how changes in breeding habitat affect female quality could help to identify management actions that would facilitate recovery of scaup populations. Advisors/Committee Members: Clark, Robert G., Chilton, Neil B., Machin, Karen L., Slattery, Stuart M., Wiebe, Karen L..

Subjects/Keywords: Ecology; avian; lesser scaup; boreal forest; offspring survival; food resources; timing of breeding

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APA (6^th Edition):

Gurney, K. (2011). Reproductive ecology of temperate-nesting waterfowl : temporal and spatial patterns of investment and success in lesser scaup (Aythya affinis) (AYTHYA AFFINIS). (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2012-05-152

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gurney, Kirsty. “Reproductive ecology of temperate-nesting waterfowl : temporal and spatial patterns of investment and success in lesser scaup (Aythya affinis) (AYTHYA AFFINIS).” 2011. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/ETD-2012-05-152.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Vancouver:

Gurney K. Reproductive ecology of temperate-nesting waterfowl : temporal and spatial patterns of investment and success in lesser scaup (Aythya affinis) (AYTHYA AFFINIS). [Internet] [Thesis]. University of Saskatchewan; 2011. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/ETD-2012-05-152.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gurney K. Reproductive ecology of temperate-nesting waterfowl : temporal and spatial patterns of investment and success in lesser scaup (Aythya affinis) (AYTHYA AFFINIS). [Thesis]. University of Saskatchewan; 2011. Available from: http://hdl.handle.net/10388/ETD-2012-05-152

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

18. Cuddington, Amber Dawne. Bio-economic considerations for wetland policy on an agricultural landscape.

Degree: 2008, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-05202008-171738

► This study looks at land use allocation and wetland management on an agricultural landscape in the Canada’s Prairie Pothole Region (PPR) within the context of… (more)

Subjects/Keywords: Law; Wetlands; Carbon; Agricultural Economics; Environment; Public Policy

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APA (6^th Edition):

Cuddington, A. D. (2008). Bio-economic considerations for wetland policy on an agricultural landscape. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-05202008-171738

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Cuddington, Amber Dawne. “Bio-economic considerations for wetland policy on an agricultural landscape.” 2008. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-05202008-171738.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Cuddington, Amber Dawne. “Bio-economic considerations for wetland policy on an agricultural landscape.” 2008. Web. 18 Jan 2021.

Vancouver:

Cuddington AD. Bio-economic considerations for wetland policy on an agricultural landscape. [Internet] [Thesis]. University of Saskatchewan; 2008. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-05202008-171738.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cuddington AD. Bio-economic considerations for wetland policy on an agricultural landscape. [Thesis]. University of Saskatchewan; 2008. Available from: http://hdl.handle.net/10388/etd-05202008-171738

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

19. Harriman, Vanessa. Seasonal Variation in Quality and Survival of Nestling Tree Swallows (Tachycineta bicolor): Tests of Alternate Hypotheses.

Degree: 2014, University of Saskatchewan

URL: http://hdl.handle.net/10388/ETD-2014-09-1696

► Understanding the patterns and processes that create differences among individuals in components of fitness, like the probability of survival or reproductive rates, is essential to… (more)

▼ Understanding the patterns and processes that create differences among individuals in components of fitness, like the probability of survival or reproductive rates, is essential to our knowledge of population dynamics and for informing conservation efforts. For organisms in seasonal environments, early-breeding individuals regularly attain higher fitness than their late-breeding counterparts. Two primary hypotheses, related to quality and date, have been proposed to explain lower reproductive success of late breeders, but the veracity of these ideas has not been fully resolved. I tested predictions associated with these hypotheses to assess the effects of indices of parental and environmental quality on nestling quality and survival in an insectivorous passerine, the tree swallow (Tachycineta bicolor), at two widely separated breeding locations in western Canada. I combined experiments and statistical modelling of observational data to evaluate two mechanisms proposed to contribute to seasonal decline in environmental quality: an increase in nest parasite abundance and a decrease in food abundance with later breeding dates. A parasite reduction experiment revealed a disproportionate benefit of parasite removal on length of primary feather for early-hatched nestlings, suggesting greater energetic constraints early in the breeding season. Furthermore, late-hatched nestlings from parasite-reduced nests had longer head-bill lengths than their control counterparts, and developed head-bills of similar length to those of early-hatched nestlings. Other than these findings, there were few detectable effects of parasites on nestling size, growth and immunity, as has been reported from several previous studies. Indeed, negative effects of parasites were only apparent when food (i.e., insect) biomass was considered. In a second series of experiments in which parental quality was controlled, I also tested whether food abundance declined during the breeding season, as predicted if environmental conditions deteriorate seasonally (i.e., date). Reduced reproductive success of late-breeding individuals was causally related to a seasonal decline in environmental quality. Declining insect biomass and enlarged brood sizes resulted in nestlings that were lighter, in poorer body condition, had shorter head-bills, shorter and slower growing ninth primary feathers and that were less likely to survive to fledge. Next, I asked whether results obtained from long-term mark-recapture data corroborated findings of short-term manipulations. I examined seasonal variation in first-year apparent survival to investigate the relative influence of large-, small- and individual-scale factors associated with the quality and date hypotheses. Although parental quality was an important predictor of first-year apparent survival of tree swallows, my results further suggested that quality of parents was not the primary factor influencing seasonal variation in first-year apparent survival. Rather, findings were most consistent with the date hypothesis. The… Advisors/Committee Members: Clark, Robert G., Dawson, Russell D., Bortolotti, Gary R., Smits, Judit E., Wobeser, Gary A., Chilton, Neil B..

Subjects/Keywords: aerial insectivore; first-year apparent survival; climate; date hypothesis; environmental quality; food; life-history theory; nest parasites; nestling quality; reproductive success; timing of breeding; tree swallow; Tachycineta bicolor; parental quality; quality hypothesis; seasonality; weather

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APA (6^th Edition):

Harriman, V. (2014). Seasonal Variation in Quality and Survival of Nestling Tree Swallows (Tachycineta bicolor): Tests of Alternate Hypotheses. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2014-09-1696

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Harriman, Vanessa. “Seasonal Variation in Quality and Survival of Nestling Tree Swallows (Tachycineta bicolor): Tests of Alternate Hypotheses.” 2014. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/ETD-2014-09-1696.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Harriman, Vanessa. “Seasonal Variation in Quality and Survival of Nestling Tree Swallows (Tachycineta bicolor): Tests of Alternate Hypotheses.” 2014. Web. 18 Jan 2021.

Vancouver:

Harriman V. Seasonal Variation in Quality and Survival of Nestling Tree Swallows (Tachycineta bicolor): Tests of Alternate Hypotheses. [Internet] [Thesis]. University of Saskatchewan; 2014. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/ETD-2014-09-1696.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Harriman V. Seasonal Variation in Quality and Survival of Nestling Tree Swallows (Tachycineta bicolor): Tests of Alternate Hypotheses. [Thesis]. University of Saskatchewan; 2014. Available from: http://hdl.handle.net/10388/ETD-2014-09-1696

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

20. Raquel, Amelia Jaclyn 1992-. Patterns of Duck Community Composition in the Prairie Pothole Region of Canada: Effects of Climate and Land Use.

Degree: 2016, University of Saskatchewan

URL: http://hdl.handle.net/10388/7641

► Shifts in the duck community composition in the Canadian Prairie Pothole Region (PPR) have been evident over the past 25 years for reasons that are… (more)

▼ Shifts in the duck community composition in the Canadian Prairie Pothole Region (PPR) have been evident over the past 25 years for reasons that are not entirely clear. Several duck species have increased in abundance whereas others have remained stable, or have declined, despite shifts in agricultural land use from annually tilled cropland to more pasture and haylands, and increases in spring pond counts since 2008. I considered three main hypotheses that could account for species-specific changes in duck abundances within the Canadian PPR; (i) redistribution; (ii) climate and (iii) land use. First, I examined whether shifts in populations of eleven duck species (seven dabbling ducks, four diving ducks) could be due to redistribution from other regions either to or from the Canadian PPR. I found no support for this hypothesis for any species. Trends and timing of changes in duck abundances were generally similar and coincident in US prairie, Canadian PPR and southern boreal forest biomes in all species. To test for effects of variations in climate, I used >20,000 nesting records for eight upland nesting duck species and related the timing of nesting and subsequent nest success to annual variations in spring temperature and moisture conditions. Furthermore, I tested for the relative importance of antecedent winter climate on nesting activities using winter El Niño Southern Oscillation indices. In general, nesting occurred earlier in warmer springs and following warmer, wetter winters. However, the magnitude of responses varied, indicating species-specific responses to variations in climate. Early nesting was the most influential factor for increasing nest survival and because timing advanced following wetter winters, this may provide a cross-seasonal mechanism for how winter climate can subsequently impact offspring recruitment in species like mallard (Anas platyrhynchos). To evaluate the land use change hypothesis, I related changes in duck abundances to changes in ponds and upland habitat composition using unique monitoring data collected in the PPR in 1985 and 2011. I used data from 42 transects distributed across the PPR to first characterize changes in upland habitat and then relate these changes to abundances of four common dabbling duck species. Pond abundances increased between ~1985 and ~2011, and cropland was converted to tame grass (i.e., pastureland). Changes in abundances of mallard and northern shoveler (A. clypeata) were primarily driven by changes in pond abundances. In blue-winged teal (A. discors), abundances of breeding birds increased more rapidly than other species and there was some evidence that conversion of cropland to tame grass resulted in greater teal abundances. Change in abundance of northern pintail (A. acuta) was not related to changes in ponds or upland habitat conditions. Overall, I found no evidence for the redistribution hypothesis; however, I did find evidence for species-specific responses to both variations in climate and changes in land use. This implies that species… Advisors/Committee Members: Clark, Robert G, Wei, Yangdou D, Johnstone, Jill F, Gurney, Kirsty EB, Guo, Xulin, Brua, Robert B.

Subjects/Keywords: waterfowl; Prairie Pothole Region; climate change; land use change

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APA (6^th Edition):

Raquel, A. J. 1. (2016). Patterns of Duck Community Composition in the Prairie Pothole Region of Canada: Effects of Climate and Land Use. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/7641

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Raquel, Amelia Jaclyn 1992-. “Patterns of Duck Community Composition in the Prairie Pothole Region of Canada: Effects of Climate and Land Use.” 2016. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/7641.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Raquel, Amelia Jaclyn 1992-. “Patterns of Duck Community Composition in the Prairie Pothole Region of Canada: Effects of Climate and Land Use.” 2016. Web. 18 Jan 2021.

Vancouver:

Raquel AJ1. Patterns of Duck Community Composition in the Prairie Pothole Region of Canada: Effects of Climate and Land Use. [Internet] [Thesis]. University of Saskatchewan; 2016. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/7641.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Raquel AJ1. Patterns of Duck Community Composition in the Prairie Pothole Region of Canada: Effects of Climate and Land Use. [Thesis]. University of Saskatchewan; 2016. Available from: http://hdl.handle.net/10388/7641

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

21. Pitt, Justin Alan. The edge of a species' range : survival and space-use patterns of raccoons at the northern periphery of their distribution.

Degree: 2006, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-04032006-120437

► The raccoon (Procyon lotor) is a species that has likely benefited from environmental conditions that followed European settlement of North America. As such, the raccoon… (more)

▼ The raccoon (Procyon lotor) is a species that has likely benefited from environmental conditions that followed European settlement of North America. As such, the raccoon has experienced vast range expansion during the past century, moving northward across the continent. However, little is known about the factors that currently govern the northern distribution and the ecology of raccoons at the northern edge of its range. Thus, I studied the population dynamics and social ecology of raccoons in southern Manitoba during spring, summer, and autumn, 2002-2005.To understand how intrinsic and extrinsic factors affected population dynamics, I examined how winter severity, body condition, age, and gender influenced over-winter survival of raccoons. Winter severity (measured by temperature and snow accumulation) was the most important factor influencing survival (â = 1.08, 95% CI = 0.99-1.17). Over-winter survival estimates ranged from 0.51 (95% CI: 0.41, 0.75) during the harshest winter to 0.84 (95% CI: 0.71, 0.97) during the mildest winter on record for Manitoba. There was no apparent relationship between autumn body condition and autumn food indices and no correlation between autumn and spring body condition. Adults experienced higher survival than yearlings while males had a greater chance of dying compared to females. Variation in abundance natural food items thought to be important during autumn hyperphagia are likely overwhelmed by the presence of grain as an alternative food source, as autumn body condition was constant across all years and plateaued at ca. 20% body fat. I conclude that changes in climatic conditions will likely have the greatest impact on raccoon demographics, with milder winters leading to higher survival. I also examined the spatial ecology of raccoons to determine if spacing behaviour could limit population growth and to test hypotheses regarding social tolerance and the formation of male coalition groups. Female home ranges were regularly spaced throughout the study site, with minimal spatio-temporal overlap among adult females. However, there where instances where females did display tolerance among conspecifics as well as the ability to partition areas of overlap to use them dissimilarly. While females were generally non-gregarious, plasticity in social tolerance likely precludes spacing behavior from regulating densities of this population. Male social behavior was more complex than previously described for northern populations; most adults (ca. 80%) formed a coalition pair with another male. There was little overlap among male groups and high overlap within groups. The dynamic interaction tests confirmed association in movements for male dyads. Male coalition groups formed despite females being regularly spaced, which contradicts working hypotheses of mechanisms explaining grouping behavior in male carnivores. I propose that group formation occurred because of the benefits that dominant males received through increased efficiency in territory maintenance and the increased… Advisors/Committee Members: Messier, François, Larivière, Serge, Clark, Robert G., Neal, Dick.

Subjects/Keywords: social ecology; survival; raccoons; coalitions

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APA (6^th Edition):

Pitt, J. A. (2006). The edge of a species' range : survival and space-use patterns of raccoons at the northern periphery of their distribution. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-04032006-120437

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pitt, Justin Alan. “The edge of a species' range : survival and space-use patterns of raccoons at the northern periphery of their distribution.” 2006. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-04032006-120437.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pitt, Justin Alan. “The edge of a species' range : survival and space-use patterns of raccoons at the northern periphery of their distribution.” 2006. Web. 18 Jan 2021.

Vancouver:

Pitt JA. The edge of a species' range : survival and space-use patterns of raccoons at the northern periphery of their distribution. [Internet] [Thesis]. University of Saskatchewan; 2006. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-04032006-120437.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pitt JA. The edge of a species' range : survival and space-use patterns of raccoons at the northern periphery of their distribution. [Thesis]. University of Saskatchewan; 2006. Available from: http://hdl.handle.net/10388/etd-04032006-120437

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

22. Moody, Allison Theresa. An analysis of arctic seabird trophic levels and foraging locations using stable isotopes.

Degree: 2007, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-05082007-131255

► Arctic ecosystems are vulnerable to human-induced changes such as increases in contaminant levels and climatic warming. To predict effects of these changes, it is important… (more)

▼ Arctic ecosystems are vulnerable to human-induced changes such as increases in contaminant levels and climatic warming. To predict effects of these changes, it is important to understand trophic relationships among Arctic organisms and how they change in response to time and environmental perturbations. Seabird diet can reflect relative availability and abundance of planktivorous fish and zooplankton in remote areas. The measurement of naturally occurring stable isotopes presents an alternative approach to evaluating dietary patterns of seabirds at both an individual level and at a larger, ecosystem level. Relative changes in δ13C values provided an indication of changes in consumption of benthic vs. pelagic prey and changes in δ15N values provided an indication of changes in trophic level.I investigated trophic positions of four seabirds (Thick-billed Murres (Uria lomvia); Northern Fulmars (Fulmarus glacialis); Black-legged Kittiwakes (Rissa tridactyla); and Glaucous Gulls (Larus hyperboreus)) at Prince Leopold Island, Nunavut, 1988 – 2003, using my own and previously measured stable isotope measurements in blood samples. Trophic level and space use among years differed within and among species and may be related to ice conditions and species-specific foraging strategies. The species with the most flexible foraging methods, Thick-billed Murres, varied their foraging location and trophic level the most. In 2002, fewer chicks than average for all species were fledged and Thick-billed Murre chicks were lighter than in other years; however, only murres showed a concurrent decrease in the proportion of fish in their diet. Adult body condition of murres in 2002 was positively correlated with trophic level. Breeding season dietary patterns of Thick-billed Murre adults and chicks were examined on Coats Island, Nunavut, Canada, in 2004. Adult trophic level increased slightly through the breeding season and δ13C values indicated a switch from benthic to pelagic foraging locations. Chick and adult murres did not differ in either δ15N or δ13C values; however, within a family (two parents, one chick), chicks were fed at or slightly below adult trophic level. I found little variation in stable isotope values which suggests adult murres did not preferentially select prey for either themselves or their chicks. Finally, stable isotope analysis was used to investigate winter foraging ecology of three species of alcids (Thick-billed Murres; Common Murres (U. aalge) and Razorbills (Alca torda)), off Newfoundland, Canada, 1996 – 2004. Thick-billed Murres fed at a higher trophic level than Common Murres. Razorbill δ15N values were highly variable and overlapped those of both murre species. I found no significant differences in δ13C values among the three species confirming a common spatial feeding pattern. Both murre species became depleted in 13C during winter suggesting foraging location or prey species shifted from nearshore to offshore. For Common Murres, hatching-year individuals fed at a higher… Advisors/Committee Members: Hobson, Keith A., Clark, Robert G., Bortolotti, Gary R..

Subjects/Keywords: ice cover analysis; isotopic monitoring; trophic level calculation; serially sampled individuals; dietary modelling

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APA (6^th Edition):

Moody, A. T. (2007). An analysis of arctic seabird trophic levels and foraging locations using stable isotopes. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-05082007-131255

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Moody, Allison Theresa. “An analysis of arctic seabird trophic levels and foraging locations using stable isotopes.” 2007. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-05082007-131255.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Moody, Allison Theresa. “An analysis of arctic seabird trophic levels and foraging locations using stable isotopes.” 2007. Web. 18 Jan 2021.

Vancouver:

Moody AT. An analysis of arctic seabird trophic levels and foraging locations using stable isotopes. [Internet] [Thesis]. University of Saskatchewan; 2007. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-05082007-131255.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Moody AT. An analysis of arctic seabird trophic levels and foraging locations using stable isotopes. [Thesis]. University of Saskatchewan; 2007. Available from: http://hdl.handle.net/10388/etd-05082007-131255

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

23. Gagnon, Chantal. Investigation of frugivory in North American migratory songbirds using stable carbon and nitrogen isotope analyses.

Degree: 2007, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-12202007-150408

► Several species of North American migratory songbirds reportedly experience seasonal diet shifts involving a shift from an insect diet during the breeding season to one… (more)

▼ Several species of North American migratory songbirds reportedly experience seasonal diet shifts involving a shift from an insect diet during the breeding season to one incorporating fruits during migration and non-breeding periods but the extent to which dietary plasticity occurs in migratory songbirds is poorly quantified. Thus, I used stable carbon (ä13C) and nitrogen (ä15N) isotope analyses to evaluate the timing and extent of frugivory throughout the annual life cycle of 16 species of migratory songbirds, representing wide ranges in body size and reported diets. Birds were sampled during spring and fall migration at the Delta Marsh Bird Observatory in 2003. To investigate dietary patterns, I sampled multiple tissues (muscle, liver, whole blood, claws, bone collagen, feathers) as these represent different periods of diet integration due to varying elemental turnover rates.Assuming that relatively low ä15N values represent a fruit diet and relatively high ä15N values represent an insect diet, I expected tissues representing fall migration (liver, blood, and muscle from fall-captured birds) and winter (greater coverts and claws from spring-captured birds) to have lower ä15N values than tissues representing spring migration (liver, blood, and muscle from spring-captured birds) and summer (tail feathers and claws from fall-captured birds) when fruits are presumed to be less common in songbird diets. Based on blood and claw ä15N values, there was no isotopic segregation of species I classified a priori as insectivores or omnivores. For most species, tissue ä15N values showed either no seasonal change or a shift opposite to my prediction (e.g., ä15N values higher in fall birds compared to spring birds). Boreal fruit ä15N values were lower than those for insects; however, ä15N values of agricultural fruits overlapped both boreal fruit and insect values suggesting that food web baselines did not conform to a simple (single) linear trophic-enrichment model. In Yellow-rumped Warblers (Dendroica coronata), within-tissue seasonal comparisons for liver, muscle and blood indicated a fruit diet during fall and winter and an insect diet during spring and summer; claws and feathers of birds captured in spring (representing winter diet) had unexpectedly high ä15N values. Diet-tissue isotopic discrimination factors associated with both a fruit diet and insect diet were taken from the literature and used to correct stable isotope values of tissues to putative diet because, currently, little is known about the nature of factors influencing discrimination factors to be used in simple linear dietary mixing models. There were differences in tissue ä13C and ä15N values depending on which discrimination factor was used. Based on mixing model results for tissue ä15N values, a higher proportion of insects vs. fruits was detected in the diet of Yellow-rumped Warblers for all tissues except muscle and claws. My interpretations are contingent on the fact that the available natural history information, on which guild classifications… Advisors/Committee Members: Hobson, Keith A., Marchant, Tracy A., Clark, Robert G..

Subjects/Keywords: Delta Marsh; discrimination factor; mixing model; Yellow-rumped Warbler; multiple tissues; migratory songbirds; frugivory

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APA (6^th Edition):

Gagnon, C. (2007). Investigation of frugivory in North American migratory songbirds using stable carbon and nitrogen isotope analyses. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-12202007-150408

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gagnon, Chantal. “Investigation of frugivory in North American migratory songbirds using stable carbon and nitrogen isotope analyses.” 2007. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-12202007-150408.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gagnon, Chantal. “Investigation of frugivory in North American migratory songbirds using stable carbon and nitrogen isotope analyses.” 2007. Web. 18 Jan 2021.

Vancouver:

Gagnon C. Investigation of frugivory in North American migratory songbirds using stable carbon and nitrogen isotope analyses. [Internet] [Thesis]. University of Saskatchewan; 2007. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-12202007-150408.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gagnon C. Investigation of frugivory in North American migratory songbirds using stable carbon and nitrogen isotope analyses. [Thesis]. University of Saskatchewan; 2007. Available from: http://hdl.handle.net/10388/etd-12202007-150408

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

24. Haszard, Shannon. Habitat use by white-winged and surf scoters in the Mackenzie Delta Region, Northwest Territories.

Degree: 2004, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-11292004-152440

► Apparent long-term declines of white-winged and surf scoter (Melanitta fusca and M. perspicillata) populations in the northern boreal forest have raised concern for these sea… (more)

▼ Apparent long-term declines of white-winged and surf scoter (Melanitta fusca and M. perspicillata) populations in the northern boreal forest have raised concern for these sea duck species. Reasons for population declines are not well understood but some evidence suggests that factors associated with events on the breeding grounds may be responsible. Breeding ground changes could adversely affect abiotic or biotic characteristics of upland or wetland habitats or key food sources for breeding females or ducklings, which in turn may lower productivity or recruitment. Like most boreal-nesting ducks, virtually nothing is known about wetland habitat preferences of scoters. Determining habitat features that scoters need to breed successfully, and how habitat changes in the boreal forest affect scoters, is an important step in understanding their ecology and developing conservation initiatives. Thus, my overall goal was to look for evidence of habitat selection in scoters at two spatial scales by characterizing biotic and abiotic features of areas used by scoter pairs and broods, and comparing these features with those of areas not used by scoters. Habitat characteristics and scoter use of wetlands in recently burned forest was also contrasted with unburned forest to determine whether habitat change caused by fire could affect patterns of habitat use by scoters. I used remote sensing data as a tool to delineate coarse-scale patterns of habitat use by scoter pairs and broods. Results indicate that although scoters may not settle on wetlands in areas dominated by burned vegetation two years following the fire, three years after the fire I found no difference in scoter pair or brood use between wetlands in burned and unburned upland. I found that surf and white-winged scoter pairs often co-occurred on wetlands. I was unable to find any evidence to support the prediction that scoters prefer wetlands with irregular shorelines that might enhance pair isolation and offer greater protection to ducklings from severe winds and wave action. Based on fine-scale wetland habitat characteristics, scoter pairs and broods used wetlands with more abundant food, a finding that is consistent with many other waterfowl studies. However, unlike some previous waterfowl studies, I did not find a consistent correlation between total phosphorus levels and amphipod abundance or wetland use by scoters. Very high total nitrogen to total phosphorus ratios in sampled wetlands lead me to speculate that wetlands in my study area may be phosphorus limited. I did not detect a difference in fine-scale features of wetlands surrounded by burned versus unburned vegetation. This study of scoters in the northern boreal forest was among the first to determine why scoters use specific wetlands or areas and not others. Advisors/Committee Members: Clark, Robert G., Hobson, Keith A., Alisauskas, Ray T..

Subjects/Keywords: land cover classification; forest fire; wetland productivity; habitat associations; amphipod; water chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Haszard, S. (2004). Habitat use by white-winged and surf scoters in the Mackenzie Delta Region, Northwest Territories. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-11292004-152440

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Haszard, Shannon. “Habitat use by white-winged and surf scoters in the Mackenzie Delta Region, Northwest Territories.” 2004. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-11292004-152440.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Haszard, Shannon. “Habitat use by white-winged and surf scoters in the Mackenzie Delta Region, Northwest Territories.” 2004. Web. 18 Jan 2021.

Vancouver:

Haszard S. Habitat use by white-winged and surf scoters in the Mackenzie Delta Region, Northwest Territories. [Internet] [Thesis]. University of Saskatchewan; 2004. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-11292004-152440.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Haszard S. Habitat use by white-winged and surf scoters in the Mackenzie Delta Region, Northwest Territories. [Thesis]. University of Saskatchewan; 2004. Available from: http://hdl.handle.net/10388/etd-11292004-152440

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

25. Mehl, Katherine Rose. Brood ecology and population dynamics of King Eiders.

Degree: 2004, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-07132004-133640

► Birth and death processes and the extent of dispersal directly affect population dynamics. Knowledge of ecological factors that influence these processes provides insight into natural… (more)

▼ Birth and death processes and the extent of dispersal directly affect population dynamics. Knowledge of ecological factors that influence these processes provides insight into natural selection and understanding about changes in population size. King eiders (Somateria spectabilis) breed across the arctic region of North America and winter in polar oceanic waters of the western and eastern regions of the continent. Here I studied a local population of King Eiders at Karrak Lake, Nunavut, where I used analysis of naturally-occurring stable isotopes (13C, 15N) from feathers, in conjunction with banding data, to investigate the extent of dispersal among winter areas and the influence of winter area on subsequent breeding. In addition, I used capture-mark-recapture methods to (1) investigate the relative contributions of survival and recruitment probabilities to local population dynamics, and (2) to test hypotheses about the influence of specific ecological factors on those probabilities or their components, e.g., nest success, duckling survival. Isotopic data suggested that female King Eiders were not strongly philopatric to wintering areas between years. Individuals that wintered in western seas initiated nests earlier and had slightly larger clutch sizes during early nest initiation relative to females that wintered in the east. Female condition during incubation did not vary by winter area. Female King Eiders of known breeding age were at least 3-years-old before their first breeding attempt. Age of first successful breeding attempt did not appear to be influenced by body size. However, after reaching breeding age, larger females apparently experienced greater breeding propensity. Adult survival rate (1996-2002) was estimated as 0.87 and recapture probabilities varied with time and ranged from 0.31 to 0.67. There is no evidence of survival advantages related to larger size. Population growth for this local study area was high, estimated at 20%/year with larger females contributing more to the population growth than smaller females. With continued population growth, density-dependent effects on components of recruitment appeared to emerge; the proportion of the female population that nested successfully declined with increasing population size. The probability of breeding successfully did not correlate with Mayfield estimates of nest success. To gain insight into King Eider brood ecology I, respectively, monitored 111 and 46 individually-marked ducklings from broods of 23 and 11 radio-marked King Eiders during 2000 and 2001. Total brood loss accounted for 84% of all duckling mortality with most brood loss (77%) less than 2 days after hatch. Estimated apparent survival rates of ducklings to 22 days of age were 0.10 for those that remained with radio-marked females, 0.16 for all ducklings, including those that had joined other broods, and 0.31 for broods. Ducklings brooded by larger females experienced higher survival than those brooded by smaller females, and ducklings that hatched earlier in the breeding season… Advisors/Committee Members: Alisauskas, Ray T., Plante, Yves, Forsyth, George W., Cooch, Evan, Clark, Robert G., Bortolotti, Gary R..

Subjects/Keywords: Brood ecology; duckling; King Eider; Somateria mollissima; Survival; waterfowl

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mehl, K. R. (2004). Brood ecology and population dynamics of King Eiders. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-07132004-133640

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Mehl, Katherine Rose. “Brood ecology and population dynamics of King Eiders.” 2004. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-07132004-133640.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Mehl, Katherine Rose. “Brood ecology and population dynamics of King Eiders.” 2004. Web. 18 Jan 2021.

Vancouver:

Mehl KR. Brood ecology and population dynamics of King Eiders. [Internet] [Thesis]. University of Saskatchewan; 2004. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-07132004-133640.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mehl KR. Brood ecology and population dynamics of King Eiders. [Thesis]. University of Saskatchewan; 2004. Available from: http://hdl.handle.net/10388/etd-07132004-133640

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

26. Mack, Glenn G. Variation in mallard home range size and composition in the prairie parkland region of Canada : correlates and consequences for breeding females.

Degree: 2003, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-08212003-140519

► Wetland density is believed to be an important determinant of home range size variation in mallards (Anas platyrhynchos), but hypothesized effects of upland habitat and… (more)

▼ Wetland density is believed to be an important determinant of home range size variation in mallards (Anas platyrhynchos), but hypothesized effects of upland habitat and female size and age have not been adequately evaluated. Thus, I investigated correlates and consequences of home range size variation using radio-tracking data for 131 female mallards studied on 12 Canadian prairie parkland sites, 1995-1998. Home range size and habitat composition varied within and among study areas; overall, home range size variation was best modeled to include effects of seasonal and semi-permanent wetlands (β = -0.06 ± 0.01 SE) and wood-shrub habitat (β = -0.03 ± 0.01 SE). Contrary to predictions, I obtained no support for a positive association between home range size and female body size or a negative relationship between home range size and female age. After controlling effects of wetland density, mean home range sizes were larger on study areas with lower mallard breeding pair densities. I suspect that individual home ranges were smaller in areas of high pair density because of increased intraspecific competition for breeding space. A higher proportion of wood-shrub habitat may have contributed to smaller individual home range sizes because of greater relative availability of preferred nesting habitat. Likewise, a high proportion of wetlands in home ranges could enhance access to important resources such as food, leading to smaller home range sizes. Reproductive and survival consequences were investigated using 8 variables to distinguish between three reproductive categories (females that either did not nest, nested but failed, or nested successfully) and two survival categories (dead versus alive) with discriminant function analysis. Successful females were clearly separated from non-nesting females by having smaller home ranges (95% kernel estimate) with higher percentages of wood-shrub and habitat treatment but lower percentages of seasonal and semi-permanent wetlands. Females that did not nest were further distinguished from nesting females by being younger, structurally smaller and having larger home ranges composed of higher percentages of seasonal and semi-permanent wetlands. Date of first nesting (standardized by study area) was not associated with home range composition. Survival was also unrelated to either home range composition or female attributes. Overall, breeding performance was better described by variation in landscape characteristics than by female attributes, a finding that is consistent with other recent evidence from breeding ducks. Advisors/Committee Members: Clark, Robert G., Messier, François, Brua, Robert B., Anderson, Michael G., Wobeser, Gary A..

Subjects/Keywords: habitat composition; Anas platyrhynchos; reproductive consequences; home range; mallard

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APA (6^th Edition):

Mack, G. G. (2003). Variation in mallard home range size and composition in the prairie parkland region of Canada : correlates and consequences for breeding females. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-08212003-140519

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Mack, Glenn G. “Variation in mallard home range size and composition in the prairie parkland region of Canada : correlates and consequences for breeding females.” 2003. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-08212003-140519.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Mack, Glenn G. “Variation in mallard home range size and composition in the prairie parkland region of Canada : correlates and consequences for breeding females.” 2003. Web. 18 Jan 2021.

Vancouver:

Mack GG. Variation in mallard home range size and composition in the prairie parkland region of Canada : correlates and consequences for breeding females. [Internet] [Thesis]. University of Saskatchewan; 2003. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-08212003-140519.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mack GG. Variation in mallard home range size and composition in the prairie parkland region of Canada : correlates and consequences for breeding females. [Thesis]. University of Saskatchewan; 2003. Available from: http://hdl.handle.net/10388/etd-08212003-140519

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

27. Caswell, Jason Hughes. Population biology of Ross's geese at McConnell River, Nunavut.

Degree: 2009, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-03172009-082710

► Understanding what influences movement patterns in animals is important to the understanding of colonization, range expansion, and source–sink dynamics. Ross’s geese (Chen rossii) have been… (more)

▼ Understanding what influences movement patterns in animals is important to the understanding of colonization, range expansion, and source–sink dynamics. Ross’s geese (Chen rossii) have been expanding their nesting range eastward, and, as recently as 1994, have been nesting in large numbers in such newly colonized areas. I sampled nests at the McConnell River Migratory Bird Sanctuary (MCR), the largest known Ross’s goose nesting colony outside the Queen Maud Gulf Migratory Bird Sanctuary (QMG) to estimate its nesting population size. To understand whether immigration by Ross’s geese to a new colony located outside traditional nesting areas has an adaptive basis, I compared nutritional, nesting, and survival metrics between geese nesting at the MCR and those nesting at Karrak Lake (KAR) in QMG. I hypothesized that because of longer nesting season, Ross’s geese at MCR would have more fat and protein reserves, larger clutch sizes, and greater nest success than those at KAR. Additionally, I hypothesized that population change at MCR was due largely to in situ recruitment. To better understand factors motivating dispersal, movement by Ross’s geese between nesting attempts at MCR was measured between years. I hypothesized that dispersal distance of nesting females between years t, and t+1 was a function of both a female’s own reproductive success as well as that of her neighbours. In 1997 over 23,000 Ross’s geese were counted at MCR. By 2007, population estimates (± SE) had increased to 81,408 (±12,367). Survival of both juvenile and adult geese marked at MCR was similar to those nesting at KAR; however, recovery rate estimates were greater than those for KAR. On average, Ross’s geese arrived and initiated nests at MCR seven days earlier than at KAR. Abdominal fat was lower when nest initiation date was later in both areas, but was generally greater in geese nesting at MCR. Similarly, there was more indexed protein in geese at MCR than those at KAR in 2 of 3 years. Nesting indices such as clutch size and nest success did not show a consistent area effect, which interacted with a year effect. Ross’s geese at MCR did not appear to use individual or conspecific reproductive success when deciding if or how far to disperse between years, and temporary emigration rates also did not vary based on reproductive success the previous year. Instead, variables other than prior individual or neighbour nest success influenced Ross’s goose nest site selection and colony fidelity. The number of Ross’s geese nesting at MCR increased at an average rate of 11.4% per year from 2003–2007, despite no increase (0%) from 2006 to 2007. Vital rate information gathered during this time suggests that immigration may have contributed to this growth; however, with few assumptions it can be concluded that MCR is a sustainable population. As a result, studies of geese breeding at MCR provide evidence that arctic geese are capable of successfully colonizing nesting areas great distances beyond historic range. Advisors/Committee Members: Alisauskas, Ray T., Leighton, Frederick A., Clark, Robert G., Messier, François.

Subjects/Keywords: goose; Ross's; arctic; nesting; dispersal; survival; mark re-capture; vital rate; McConnell River

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Caswell, J. H. (2009). Population biology of Ross's geese at McConnell River, Nunavut. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-03172009-082710

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Caswell, Jason Hughes. “Population biology of Ross's geese at McConnell River, Nunavut.” 2009. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-03172009-082710.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Caswell, Jason Hughes. “Population biology of Ross's geese at McConnell River, Nunavut.” 2009. Web. 18 Jan 2021.

Vancouver:

Caswell JH. Population biology of Ross's geese at McConnell River, Nunavut. [Internet] [Thesis]. University of Saskatchewan; 2009. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-03172009-082710.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Caswell JH. Population biology of Ross's geese at McConnell River, Nunavut. [Thesis]. University of Saskatchewan; 2009. Available from: http://hdl.handle.net/10388/etd-03172009-082710

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

28. Fisher, Ryan Jeffrey. Nest characteristics, breeding dispersal, and nest defence behaviour of Northern Flickers in relation to nest predation.

Degree: 2005, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-04272005-145315

► I studied nest characteristics, breeding dispersal, and nest defence behaviour of Northern Flickers (Colaptes auratus, hereafter flickers) in central interior British Columbia with respect to… (more)

▼ I studied nest characteristics, breeding dispersal, and nest defence behaviour of Northern Flickers (Colaptes auratus, hereafter flickers) in central interior British Columbia with respect to nest predation. My research focused on three questions: (1) Are there nest characteristics associated with the risk of nest predation and nest loss to European Starlings (Sturnus vulgaris)? (2) Does nest predation influence breeding dispersal? (3) Do parental attributes influence nest defence behaviour? An examination of flicker nest-site characteristics at five spatial scales revealed that nests were safer from mammalian predators (N=81) when they were higher, concealed by vegetation, farther from continuous coniferous forest blocks, and contained fewer conifers within the nesting clump. Proximity to conifers increased predation risk, but nests safe from competitors (N=18) were closer to coniferous forest blocks and contained a higher percentage of conifers in the nesting clump. Flickers face a trade-off between being safe from predators and safe from competitors. Nesting success did not influence between-year breeding dispersal by 159 male or 76 female flickers. Because nests and forest clumps were not predictably safe from predators, benefits of dispersing likely outweigh costs. Other factors such as mate-switching, nest ectoparasites, and a fluctuating food source may play larger roles in dispersal than nest predation. Within years, 73% of pairs switched nest sites after their first attempt failed due to predation (N=37); however, there was no reproductive advantage for these pairs compared to pairs that remained at their original nest. Stressful encounters with predators involving nest defence may trigger dispersal, although it seems to offer no greater nest success. Of 24 flicker pairs presented with a control model before egg-laying, 3 pairs abandoned their nest, whereas 4 out of 24 pairs presented with a squirrel model abandoned their nest. This suggests that a one-time encounter with a nest predator is not a sufficient deterrent against continued nesting. Rather, costs of finding and excavating or renovating a new cavity may cause individuals to tolerate some risk in nesting at a location with an active predator. In experimental trials (N=94), intensity of nest defence behaviour against a model predator was not related to the sex, age, body size, and body condition of the defending adult(s). The sexes may have behaved similarly because they are similar in size and have similar survival patterns. Costs and benefits of nest defence for flickers of different ages may also be equal because flickers are relatively short-lived and their survival rate is not linked with age. Brood size of the defending adult was also unrelated to the intensity of nest defence. If flickers have adjusted their clutch size in relation to the number of young for which they can optimally provide care, then no effects of brood size on nest defence behaviour should be recorded, as was the case here. Advisors/Committee Members: Wiebe, Karen L., Sealy, Spencer, Clark, Robert G., Chivers, Douglas P., Bortolotti, Gary R..

Subjects/Keywords: cavity nester; predation; woodpecker; trade-off; competition

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APA (6^th Edition):

Fisher, R. J. (2005). Nest characteristics, breeding dispersal, and nest defence behaviour of Northern Flickers in relation to nest predation. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-04272005-145315

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Fisher, Ryan Jeffrey. “Nest characteristics, breeding dispersal, and nest defence behaviour of Northern Flickers in relation to nest predation.” 2005. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-04272005-145315.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Fisher, Ryan Jeffrey. “Nest characteristics, breeding dispersal, and nest defence behaviour of Northern Flickers in relation to nest predation.” 2005. Web. 18 Jan 2021.

Vancouver:

Fisher RJ. Nest characteristics, breeding dispersal, and nest defence behaviour of Northern Flickers in relation to nest predation. [Internet] [Thesis]. University of Saskatchewan; 2005. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-04272005-145315.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Fisher RJ. Nest characteristics, breeding dispersal, and nest defence behaviour of Northern Flickers in relation to nest predation. [Thesis]. University of Saskatchewan; 2005. Available from: http://hdl.handle.net/10388/etd-04272005-145315

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

29. Traylor, Joshua James. Nesting and duckling ecology of white-winged scoters (melanitta fusca deglandi) at Redberry Lake, Saskatchewan.

Degree: 2003, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-11282003-140602

► Population surveys indicate a declining trend in abundance for the scoter genus at the continental level. Little is known about changes in life history traits… (more)

▼ Population surveys indicate a declining trend in abundance for the scoter genus at the continental level. Little is known about changes in life history traits responsible for the recent population decline of white-winged scoters (Melanitta fusca deglandi, hereafter scoters). Therefore, I studied nesting and duckling ecology of scoters at Redberry Lake, Saskatchewan, Canada during summers 2000-2001 when I found 198 nests. To examine nest-site selection, I compared habitat features between successful nests, failed nests, and random sites. Discriminant function analysis differentiated habitat features, measured at hatch, between successful nests, failed nests, and random sites; lateral (r = 0.65) and overhead (r = 0.35) concealment were microhabitat variables most correlated with canonical discriminant functions. I also modeled daily survival rate (DSR) of nests as a function of year, linear and quadratic trends with nest age, nest initiation date, and seven microhabitat variables. Nest survival from a time constant model (i.e., Mayfield nest success estimate) was 0.35 (95% CL: 0.27, 0.43). Estimates of nest success were lower than those measured at Redberry Lake in the 1970s and 1980s. In addition to nest survival increasing throughout the laying period and stabilizing during incubation, nest survival showed positive relationships with nest concealment and distance to water, and a negative relationship with distance to edge. Considering these factors, a model-averaged estimate of nest survival was 0.24 (95% CL: 0.09, 0.42). I conclude that scoters selected nesting habitat adaptively because (1) successful sites were more concealed than failed sites, (2) nest sites (i.e., successful and failed) had higher concealment than random sites, and (3) nest sites were on islands where success is greater than mainland. I then estimated duckling and brood survival with Cormack-Jolly-Seber models, implemented in Program Mark, from observations of 94 and 664 individually marked adult hens and ducklings, respectively. I tested hypotheses about duckling survival and (1) hatch date, (2) initial brood size at hatch, (3) duckling size and body condition at hatch, (4) offspring sex, (5) maternal female size and body condition at hatch, and (6) weather conditions within one week of hatching. Most mortality occurred during the first six days of duckling age. Variation in both duckling and brood survival were best modeled with effects of hatch date and initial brood size, while effects of female condition, female size, duckling size, and duckling condition were inconsistent. Survival probability clearly decreased with advancing hatch date and increased with larger initial brood sizes. Effects of weather and offspring sex in 2001, the only year such information was collected, suggested survival was negatively related to poor weather, but sex of ducklings, beyond size-related differences (i.e., sexual-size dimorphism), was unimportant. Estimates of survival to 28 days of age (30-day period), whether for ducklings (0.016,… Advisors/Committee Members: Alisauskas, Ray T., Hill, Michael, Clark, Robert G., Chivers, Douglas P., Messier, François.

Subjects/Keywords: nest survival; duckling survival; cormack-jolly-seber models; Program MARK; nesting success

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Traylor, J. J. (2003). Nesting and duckling ecology of white-winged scoters (melanitta fusca deglandi) at Redberry Lake, Saskatchewan. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-11282003-140602

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Traylor, Joshua James. “Nesting and duckling ecology of white-winged scoters (melanitta fusca deglandi) at Redberry Lake, Saskatchewan.” 2003. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-11282003-140602.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Traylor, Joshua James. “Nesting and duckling ecology of white-winged scoters (melanitta fusca deglandi) at Redberry Lake, Saskatchewan.” 2003. Web. 18 Jan 2021.

Vancouver:

Traylor JJ. Nesting and duckling ecology of white-winged scoters (melanitta fusca deglandi) at Redberry Lake, Saskatchewan. [Internet] [Thesis]. University of Saskatchewan; 2003. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-11282003-140602.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Traylor JJ. Nesting and duckling ecology of white-winged scoters (melanitta fusca deglandi) at Redberry Lake, Saskatchewan. [Thesis]. University of Saskatchewan; 2003. Available from: http://hdl.handle.net/10388/etd-11282003-140602

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

30. Swoboda, Cindy Jean. Population delineation and wintering ground influence on vital rates of white-winged scoters.

Degree: 2007, University of Saskatchewan

URL: http://hdl.handle.net/10388/etd-05022007-145956

► North American populations of white-winged scoters (Melanitta fusca deglandi) have declined markedly over the past several decades. The causes for decline are uncertain, but likely… (more)

▼ North American populations of white-winged scoters (Melanitta fusca deglandi) have declined markedly over the past several decades. The causes for decline are uncertain, but likely involve a complexity of events occurring on wintering and breeding areas. To gain insight into potential cross-seasonal effects, I delineated Atlantic and Pacific wintering scoter populations and linked them to a shared breeding area using stable isotope analysis of carbon (δ13C) and nitrogen (δ15N) ratios in feathers. By applying this methodology to a marked breeding population at Redberry Lake, Saskatchewan, I assigned females to putative wintering areas and determined: (1) population structure; (2) the extent of winter site philopatry; and, (3) differences in vital rates and other variates in relation to winter origin. Discriminant function analysis of isotopic ratios in feather samples from known wintering locations resulted in classification probabilities of 96% (n = 149) for Pacific and 78% (n = 32) for Atlantic wintering scoters. Using this methodology, I determined that the Redberry Lake breeding population is comprised of approximately 75% Pacific and 25% Atlantic wintering birds, and its members exhibit high degrees of winter region philopatry based on the classification of successive recaptures over three field seasons. Annual variations in population structure, as well as differences in nest initiation dates and blood contaminant loads in relation to winter area suggest seasonal interactions may influence survival and reproductive success of this population. To gain insight into potential seasonal interactions, I examined nest success and female survival in relation to winter area. No significant differences in nest success in relation to winter area were found, but nests that failed before mid-incubation were not sampled. Adult female survival rate for 2000-2004 was estimated as 0.85, with no significant difference detected between wintering areas. This study demonstrated that it is important to link breeding and wintering areas to better understand the factors influencing population dynamics and to effectively address conservation issues. Advisors/Committee Members: Alisauskas, Ray T., Hobson, Keith A., Clark, Robert G., Chivers, Douglas P..

Subjects/Keywords: Melanitta fusca deglandi; White-winged Scoters; δ15N; nitrogen-15; carbon-13; δ13C; stable isotopes; population delineation; philopatry; cross-seasonal effects; blood contaminants

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Swoboda, C. J. (2007). Population delineation and wintering ground influence on vital rates of white-winged scoters. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-05022007-145956

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Swoboda, Cindy Jean. “Population delineation and wintering ground influence on vital rates of white-winged scoters.” 2007. Thesis, University of Saskatchewan. Accessed January 18, 2021. http://hdl.handle.net/10388/etd-05022007-145956.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Swoboda, Cindy Jean. “Population delineation and wintering ground influence on vital rates of white-winged scoters.” 2007. Web. 18 Jan 2021.

Vancouver:

Swoboda CJ. Population delineation and wintering ground influence on vital rates of white-winged scoters. [Internet] [Thesis]. University of Saskatchewan; 2007. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10388/etd-05022007-145956.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Swoboda CJ. Population delineation and wintering ground influence on vital rates of white-winged scoters. [Thesis]. University of Saskatchewan; 2007. Available from: http://hdl.handle.net/10388/etd-05022007-145956

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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