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University of Alberta
1.
Fortin, Barbra Linda.
Selenium dynamics in Canadian Rocky Mountain lakes.
Degree: MS, Department of Biological Sciences, 2010, University of Alberta
URL: https://era.library.ualberta.ca/files/ng451j405
► I investigated, water, invertebrates and fishes from lakes in Banff National Park and Kananaskis Country, Alberta for selenium (Se), an element known to be toxic…
(more)
▼ I investigated, water, invertebrates and fishes from
lakes in Banff National Park and Kananaskis Country, Alberta for
selenium (Se), an element known to be toxic to vertebrates. At some
depths, Se concentrations in sediment exceeded recognized
thresholds for bird and fish reproductive impairment. Se
concentrations in water were over USEPA guidelines after spring
melt runoff. In aquatic invertebrates, Se concentrations exceeded
values known to cause reproductive impairment in fish and bird
predators. Se concentrations in all fish species exceeded known
thresholds for reproductive impairment in avian consumers and the
majority surpassed concentrations that would negatively affect
wildlife and human consumers. Se concentrations in some fish
species have significantly increased over the past 6-16 years. The
strongest predictors of fish Se concentrations were growth rate,
condition factor, age, weight, trophic position (within lakes) and
vegetation type (among lakes). These results suggest that
consumption advisories are desirable for several lakes in the Banff
and Kananaskis area, and that Se concentrations in fish from other
area lakes should be investigated.
Subjects/Keywords: fishes; selenium; mountain; food web
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APA (6th Edition):
Fortin, B. L. (2010). Selenium dynamics in Canadian Rocky Mountain lakes. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/ng451j405
Chicago Manual of Style (16th Edition):
Fortin, Barbra Linda. “Selenium dynamics in Canadian Rocky Mountain lakes.” 2010. Masters Thesis, University of Alberta. Accessed April 11, 2021.
https://era.library.ualberta.ca/files/ng451j405.
MLA Handbook (7th Edition):
Fortin, Barbra Linda. “Selenium dynamics in Canadian Rocky Mountain lakes.” 2010. Web. 11 Apr 2021.
Vancouver:
Fortin BL. Selenium dynamics in Canadian Rocky Mountain lakes. [Internet] [Masters thesis]. University of Alberta; 2010. [cited 2021 Apr 11].
Available from: https://era.library.ualberta.ca/files/ng451j405.
Council of Science Editors:
Fortin BL. Selenium dynamics in Canadian Rocky Mountain lakes. [Masters Thesis]. University of Alberta; 2010. Available from: https://era.library.ualberta.ca/files/ng451j405

University of Canterbury
2.
Graham, Sharon Elizabeth.
Mechanisms and mitigation of food web change in stream ecosystems.
Degree: PhD, Ecology, 2013, University of Canterbury
URL: http://dx.doi.org/10.26021/7565
► Freshwater ecosystems reflect the condition of their surrounding landscape, and thus are particularly vulnerable to anthropogenic stressors associated with human land-use. One of the most…
(more)
▼ Freshwater ecosystems reflect the condition of their surrounding landscape, and thus are particularly vulnerable to anthropogenic stressors associated with human land-use. One of the most prevalent stressors on stream ecosystems in agricultural regions, such as the Canterbury Plains of New Zealand, is eutrophication, or increased primary productivity. The aim of this thesis was to investigate effects of eutrophication on stream communities, specifically food web structure and ecosystem function. From a food web perspective, eutrophication is a shift in the form and amount of available energy from externally-produced (allochthonous) to internal (autochthonous) basal resources. Such shifts are frequently associated with land-use intensification, due to riparian vegetation removal and increased nutrient inputs, both of which enhance autochthonous production. A field survey across a gradient of eutrophication showed that eutrophic stream food webs are largely autochthonously-based and often contain large numbers of defended primary consumers, which form trophic bottlenecks and prevent energy from reaching higher trophic levels. Consequently, while there is more total energy available, less of that energy is in a usable form for stream food webs. Moreover, I found that eutrophic streams are largely composed of generalist consumers, which shift their diets to refocus on autochthonous resources with increasing productivity. Given that eutrophication causes food web resources to become more homogenous and was a primary driver of food web change, I tested whether reintroducing allochthonous subsidies would alter or reverse the negative effects of eutrophication. To do this I conducted a short-term community assembly experiment and a year-long population biomass accrual study. I found that the simplified, generalist-dominated communities in eutrophic streams did not respond to changes in resource diversity as predicted by food web theories, which are based on more diverse food webs. After restoration of allochthonous subsidies, defended generalist taxa continued to dominate the invertebrate communities. However, while restoring allochthonous subsidies did not mitigate the numerical dominance of defended consumers, the biomass accrual of other, previously excluded desirable taxa, such as mayflies and predatory invertebrates, increased following resource additions. This indicates that more energy reached the top of the food web, suggesting that resource additions alleviated trophic bottlenecks. Overall, my findings have advanced current knowledge about key mechanisms driving food web responses to both anthropogenic stress and to restoration efforts, which can be applied to improve management and restoration of stream ecosystems.
Subjects/Keywords: stream; ecology; food web; eutrophication
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
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APA (6th Edition):
Graham, S. E. (2013). Mechanisms and mitigation of food web change in stream ecosystems. (Doctoral Dissertation). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/7565
Chicago Manual of Style (16th Edition):
Graham, Sharon Elizabeth. “Mechanisms and mitigation of food web change in stream ecosystems.” 2013. Doctoral Dissertation, University of Canterbury. Accessed April 11, 2021.
http://dx.doi.org/10.26021/7565.
MLA Handbook (7th Edition):
Graham, Sharon Elizabeth. “Mechanisms and mitigation of food web change in stream ecosystems.” 2013. Web. 11 Apr 2021.
Vancouver:
Graham SE. Mechanisms and mitigation of food web change in stream ecosystems. [Internet] [Doctoral dissertation]. University of Canterbury; 2013. [cited 2021 Apr 11].
Available from: http://dx.doi.org/10.26021/7565.
Council of Science Editors:
Graham SE. Mechanisms and mitigation of food web change in stream ecosystems. [Doctoral Dissertation]. University of Canterbury; 2013. Available from: http://dx.doi.org/10.26021/7565

Cornell University
3.
Fetzer, William.
Disentangling The Effects Of Multiple Ecosystem Changes On Fish Population And Community Dynamics.
Degree: PhD, Natural Resources, 2013, Cornell University
URL: http://hdl.handle.net/1813/34379
► North temperate lakes are undergoing diverse physical, chemical, and biological changes, including warming water temperatures, shifts in lake trophic states, and introductions of non-native species.…
(more)
▼ North temperate lakes are undergoing diverse physical, chemical, and biological changes, including warming water temperatures, shifts in lake trophic states, and introductions of non-native species. These ecosystem perturbations rarely occur in isolation, making it difficult to evaluate the impacts of concurrent perturbations on population and community dynamics. Here, I use Oneida Lake, New York, USA, to study interactions among multiple ecological changes and their combined effects on age-0 and juvenile yellow perch (Perca flavescens). These ecological changes included diversification of the predator and prey communities, shifts in lake trophic state from eutrophic to mesotrophic, and an expansion of littoral habitats. Multiple long-term limnological and fisheries datasets were integrated with short-term diet studies of age-0 yellow perch and their predators from nearshore and offshore habitats to develop a multi-habitat understanding of lake-wide responses to ecosystem perturbations. Walleye (Sander vitreus) were still the most important predator on age-0 and juvenile yellow perch, though the importance of alternative predators, such as white perch (Morone americana), smallmouth bass (Micropterus dolomieu), and largemouth bass (Micropterus salmoides), was also high and has likely increased. Consumption of age-0 yellow perch was dominated by walleye and white perch in offshore habitats during early summer, but transitioned to walleye, smallmouth bass, and largemouth bass in nearshore habitats during the fall and second year of life. As ecological conditions within the lake changed, age-0 yellow perch population dynamics became increasingly driven by littoral habitats and the population-level reliance on benthic energy pathways increased from 10-20% in the 1960s to 30-70% in the 2000s. These results illustrate the importance of both nearshore and offshore habitats to age-0 and juvenile yellow perch population dynamics and highlight the complexity of population- and community-level responses to ecosystem perturbations.
Advisors/Committee Members: Rudstam, Lars Gosta (chair), Rudstam, Lars Gosta (chair), Sullivan, Patrick J (committee member), Mills, Edward Lewis (committee member), Flecker, Alexander S (committee member), Sullivan, Patrick J (committee member), Decker, Daniel Joseph (committee member), Jackson, James R. (committee member).
Subjects/Keywords: food web dynamics; aquatic ecology; individual specialization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fetzer, W. (2013). Disentangling The Effects Of Multiple Ecosystem Changes On Fish Population And Community Dynamics. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/34379
Chicago Manual of Style (16th Edition):
Fetzer, William. “Disentangling The Effects Of Multiple Ecosystem Changes On Fish Population And Community Dynamics.” 2013. Doctoral Dissertation, Cornell University. Accessed April 11, 2021.
http://hdl.handle.net/1813/34379.
MLA Handbook (7th Edition):
Fetzer, William. “Disentangling The Effects Of Multiple Ecosystem Changes On Fish Population And Community Dynamics.” 2013. Web. 11 Apr 2021.
Vancouver:
Fetzer W. Disentangling The Effects Of Multiple Ecosystem Changes On Fish Population And Community Dynamics. [Internet] [Doctoral dissertation]. Cornell University; 2013. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/1813/34379.
Council of Science Editors:
Fetzer W. Disentangling The Effects Of Multiple Ecosystem Changes On Fish Population And Community Dynamics. [Doctoral Dissertation]. Cornell University; 2013. Available from: http://hdl.handle.net/1813/34379

University of Waterloo
4.
Ives, Jessica.
Isotopic niche use by the invasive mysid Hemimysis anomala in the Laurentian Great Lakes basin.
Degree: 2013, University of Waterloo
URL: http://hdl.handle.net/10012/7518
► Invasive species are a known stressor on aquatic ecosystems, particularly in the waters of the Great Lakes basin. A recent invader, Hemimysis anomala, has had…
(more)
▼ Invasive species are a known stressor on aquatic ecosystems, particularly in the waters of the Great Lakes basin. A recent invader, Hemimysis anomala, has had significant impacts on the food webs of Europe, where it invaded previous to its spread to North America. However, despite the fact that Hemimysis is now widespread in the Great Lakes basin, no analysis has been done on the trophic position of Hemimysis in North America invaded sites. This thesis used carbon (δ13C) and nitrogen (δ15N) stable isotopes to examine spatial and temporal patterns in Hemimysis trophic niche use in invaded North American sites in an attempt to broaden the knowledge base on this invader and to examine potential impacts this invader may have on the food webs of the Great Lakes.
A spatial comparison of trophic niche use by Hemimysis among 13 sites in Lake Erie, Lake Ontario, and the St. Lawrence River was conducted between late July and mid-September of 2011. Main sources of carbon (benthic versus pelagic production) and trophic offset, or trophic distance from basal food web items, of Hemimysis were quantified using Hemimysis δ13C and δ15N values. Results indicated that: 1) Hemimysis relied predominantly on pelagic carbon sources at the majority of sites, and isotopic differences between life-stages existed at two of the 13 sites examined, 2) the trophic offset and reliance on pelagic food sources did not differ significantly between lotic and lentic sites, and 3) the isotopic niche width of Hemimysis was spatially heterogeneous, varying by an order of magnitude among sites, but was unrelated to the degree of isotopic variation in the basal food web at each site. Observed ranges in trophic offset and the pelagic fraction of dietary carbon indicate that Hemimysis derives carbon from both benthic and water column sources, as well as at multiple trophic levels. Results support the notion that Hemimysis is an opportunistic omnivore that displays significant dietary flexibility.
To test the relative importance of key biotic and abiotic factors, taken from the literature, in driving Hemimysis isotopic variation, a temporal analysis was conducted at two North American sites, one in Lake Ontario and one in the St. Lawrence River, which were repeatedly sampled for Hemimysis and related food web items between September 2008 and January 2012. Seasonal patterns of winter enrichment – summer depletion were found in Hemimysis δ15N in Lake Ontario, but a similar pattern was not seen in the St. Lawrence River. Multiple regression models were used to determine the importance of water temperature, Hemimysis C:N ratios, Hemimysis length, and the isotopic values of basal food web components in explaining observed variation in Hemimysis δ13C and δ15N values. Significant relationships were found between Hemimysis isotopic values and water temperature, but relationships with the isotopic signatures of the pelagic basal food web were weak or nonexistent. Hemimysis δ13C values were significantly correlated with C:N ratios. Strong evidence of an ontogenetic…
Subjects/Keywords: stable isotopes; invasive species; food web
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ives, J. (2013). Isotopic niche use by the invasive mysid Hemimysis anomala in the Laurentian Great Lakes basin. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/7518
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ives, Jessica. “Isotopic niche use by the invasive mysid Hemimysis anomala in the Laurentian Great Lakes basin.” 2013. Thesis, University of Waterloo. Accessed April 11, 2021.
http://hdl.handle.net/10012/7518.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ives, Jessica. “Isotopic niche use by the invasive mysid Hemimysis anomala in the Laurentian Great Lakes basin.” 2013. Web. 11 Apr 2021.
Vancouver:
Ives J. Isotopic niche use by the invasive mysid Hemimysis anomala in the Laurentian Great Lakes basin. [Internet] [Thesis]. University of Waterloo; 2013. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/10012/7518.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ives J. Isotopic niche use by the invasive mysid Hemimysis anomala in the Laurentian Great Lakes basin. [Thesis]. University of Waterloo; 2013. Available from: http://hdl.handle.net/10012/7518
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queens University
5.
Poulopoulos, John.
Long-term changes to food web structures and mercury biomagnification in three large, inland North American lakes
.
Degree: Biology, 2013, Queens University
URL: http://hdl.handle.net/1974/7782
► Numerous anthropogenic disturbances have occurred in large lakes over recent decades. These may alter concentrations of the biomagnifying contaminant mercury (Hg) in fish, but long-term…
(more)
▼ Numerous anthropogenic disturbances have occurred in large lakes over recent decades. These may alter concentrations of the biomagnifying contaminant mercury (Hg) in fish, but long-term impacts of disturbances on Hg trophodynamics are poorly understood. Elemental analyses of archived museum ichthyology specimens could be used to study historical, pre-disturbance fish food webs, but there is uncertainty about effects of chemical preservatives on the results of such analyses. In this thesis, long-term preservation effects were studied, and archived fish were used to reconstruct historical food webs and Hg trophodynamic patterns in three large North American lakes, Nipigon, Simcoe and Champlain. After 24 months of formalin/ethanol preservation, fish muscle delta-15N and delta-13C had average changes of +0.4 ‰ and -0.9 ‰, respectively. Shifts in mean Hg concentration was +5 % after 12 months. A suite of 26 other elements analyzed over 24 months showed consistent responses to preservation, usually involving an increase in concentration immediately following preservation. In the second phase of the thesis, stable isotope and Hg analyses were performed on archived and modern fish from the study lakes, dating to the 1920s-60s and 2006-7, respectively. Trophic relationships were often relatively stable over time, but stable isotope metrics revealed a decrease in Lake Nipigon delta-15N range and less pelagic feeding among Lake Simcoe pumpkinseed and yellow perch. In Lake Champlain, the re-introduction of lake trout in recent decades did not have a major effect on overall food web dimensions. Significant Hg biomagnification factors were found in 1920s and 2006-7 Lake Nipigon (which were not statistically distinguishable from each other) and 2006 Lake Champlain. These biomagnification factors ranged from 0.09 to 0.17, which is within the range found in other studies globally. Archived fish and government monitoring records indicated that fish Hg concentrations decreased in Lakes Simcoe and Champlain since historical periods, but remained similar or increased in Lake Nipigon. This thesis confirms the utility of archived fish for elemental analyses. It highlights the risks of Hg contamination and food web change that may be faced by remote lakes, and it provides evidence for relatively stable Hg biomagnification rates in large lakes.
Subjects/Keywords: food web
;
museum
;
stable isotopes
;
preservation
;
mercury
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Poulopoulos, J. (2013). Long-term changes to food web structures and mercury biomagnification in three large, inland North American lakes
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/7782
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Poulopoulos, John. “Long-term changes to food web structures and mercury biomagnification in three large, inland North American lakes
.” 2013. Thesis, Queens University. Accessed April 11, 2021.
http://hdl.handle.net/1974/7782.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Poulopoulos, John. “Long-term changes to food web structures and mercury biomagnification in three large, inland North American lakes
.” 2013. Web. 11 Apr 2021.
Vancouver:
Poulopoulos J. Long-term changes to food web structures and mercury biomagnification in three large, inland North American lakes
. [Internet] [Thesis]. Queens University; 2013. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/1974/7782.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Poulopoulos J. Long-term changes to food web structures and mercury biomagnification in three large, inland North American lakes
. [Thesis]. Queens University; 2013. Available from: http://hdl.handle.net/1974/7782
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Montana Tech
6.
Staats, Molly Frances.
FACTORS AFFECTING MERCURY BIOMAGNIFICATION IN RIVERINE FOOD WEBS IN THE ROCKY MOUNTAINS: CLARK FORK RIVER BASIN, MONTANA, U.S.A.
Degree: MS, 2011, Montana Tech
URL: https://scholarworks.umt.edu/etd/1328
► A number of studies suggest that Hg biomagnification in aquatic systems are dependent on two factors: a source of mercury and the potential for this…
(more)
▼ A number of studies suggest that Hg biomagnification in aquatic systems are dependent on two factors: a source of mercury and the potential for this mercury to become methylated. To compare the importance of these two factors in a riverine system I examine sites with varying sediment total mercury concentrations (source term) and varying environmental conditions affecting mercury methylation (wetland abundance, and riparian abundance) resulting in mercury concentration in three riverine trophic levels (aquatic invertebrates, fish, and osprey). I find that the mercury concentrations of low trophically positioned species, like aquatic invertebrates, are extremely dependent on mercury source concentrations (p=0.0143). While, species in subsequent trophic positions, such as fish see substantial influence from both the source term (p<0.0001) and environmental conditions (wetland abundance, p<0.0001 and riparian abundance, p=0.0008. Top trophic level species, such as osprey, have THg concentrations that are heavily dependent on environmental conditions (wetland abundance p<0.0001 and riparian abundance, p=0.0001) and less on the sediment source of THg (p=.1234). Specifically, for these higher trophic levels, wetland abundance is the most explanatory environmental condition in determining the mercury methylation potential.
Subjects/Keywords: biomagnification; food web; mercury; mercuy methylation; wetlands
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
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to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Staats, M. F. (2011). FACTORS AFFECTING MERCURY BIOMAGNIFICATION IN RIVERINE FOOD WEBS IN THE ROCKY MOUNTAINS: CLARK FORK RIVER BASIN, MONTANA, U.S.A. (Masters Thesis). Montana Tech. Retrieved from https://scholarworks.umt.edu/etd/1328
Chicago Manual of Style (16th Edition):
Staats, Molly Frances. “FACTORS AFFECTING MERCURY BIOMAGNIFICATION IN RIVERINE FOOD WEBS IN THE ROCKY MOUNTAINS: CLARK FORK RIVER BASIN, MONTANA, U.S.A.” 2011. Masters Thesis, Montana Tech. Accessed April 11, 2021.
https://scholarworks.umt.edu/etd/1328.
MLA Handbook (7th Edition):
Staats, Molly Frances. “FACTORS AFFECTING MERCURY BIOMAGNIFICATION IN RIVERINE FOOD WEBS IN THE ROCKY MOUNTAINS: CLARK FORK RIVER BASIN, MONTANA, U.S.A.” 2011. Web. 11 Apr 2021.
Vancouver:
Staats MF. FACTORS AFFECTING MERCURY BIOMAGNIFICATION IN RIVERINE FOOD WEBS IN THE ROCKY MOUNTAINS: CLARK FORK RIVER BASIN, MONTANA, U.S.A. [Internet] [Masters thesis]. Montana Tech; 2011. [cited 2021 Apr 11].
Available from: https://scholarworks.umt.edu/etd/1328.
Council of Science Editors:
Staats MF. FACTORS AFFECTING MERCURY BIOMAGNIFICATION IN RIVERINE FOOD WEBS IN THE ROCKY MOUNTAINS: CLARK FORK RIVER BASIN, MONTANA, U.S.A. [Masters Thesis]. Montana Tech; 2011. Available from: https://scholarworks.umt.edu/etd/1328

University of Oklahoma
7.
Lucas, Jane.
FROM COOPERATION TO COMPETITION: HOW MICROBES AND INVERTEBRATES INTERACT IN A TROPICAL FOREST.
Degree: PhD, 2018, University of Oklahoma
URL: http://hdl.handle.net/11244/299325
► Microbes and invertebrates are “the little things that run the world” (Wilson 1987, Moreau 2017), but the intricacies of how these organisms impact our environment…
(more)
▼ Microbes and invertebrates are “the little things that run the world” (Wilson 1987, Moreau 2017), but the intricacies of how these organisms impact our environment remains underexplored. Here I investigate how microbes and invertebrates interact and how these interactions scale-up to impact communities and ecosystem-level processes. This work focuses on tropical brown
food webs because they are dominated by a diversity of microbe-invertebrate relationships that span from obligate symbioses to fierce competition. Initially, I examine the symbiotic relationship between a dominant canopy ant, Azteca trigona, and their microbiota. Here I describe the diversity of microbial communities associated with these ants and demonstrate the role of invertebrate activity in microbial dispersal (Ch. 1). Furthermore, the microbial community within these canopy ants provides the basis for a facultative relationship between ants and their host plants, as the ant endosymbionts increase plant growth and facilitate nutrient exchange (Ch. 2). I then transition to explore how competition between microbes and invertebrates can shape the local community in the ephemeral environment of tropical leaf litter (Ch. 3). I demonstrate that antibiotic production by microbes—long considered a potent mechanism of competition between microbes—can also be effective against invertebrates. This cross-domain competition likely contributes to the diversity of detrital
food webs (Ch. 4). Combined, the results of these studies demonstrate how invertebrate-microbe interactions drive ecosystem structure and function.
Advisors/Committee Members: Kaspari, Michael (advisor), Stevenson, Bradley (committee member), Souza, Lara (committee member), Patten, Michael (committee member), Givel, Michael (committee member).
Subjects/Keywords: Ecology; Microbial Ecology; Invertebrate; Brown Food Web
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lucas, J. (2018). FROM COOPERATION TO COMPETITION: HOW MICROBES AND INVERTEBRATES INTERACT IN A TROPICAL FOREST. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/299325
Chicago Manual of Style (16th Edition):
Lucas, Jane. “FROM COOPERATION TO COMPETITION: HOW MICROBES AND INVERTEBRATES INTERACT IN A TROPICAL FOREST.” 2018. Doctoral Dissertation, University of Oklahoma. Accessed April 11, 2021.
http://hdl.handle.net/11244/299325.
MLA Handbook (7th Edition):
Lucas, Jane. “FROM COOPERATION TO COMPETITION: HOW MICROBES AND INVERTEBRATES INTERACT IN A TROPICAL FOREST.” 2018. Web. 11 Apr 2021.
Vancouver:
Lucas J. FROM COOPERATION TO COMPETITION: HOW MICROBES AND INVERTEBRATES INTERACT IN A TROPICAL FOREST. [Internet] [Doctoral dissertation]. University of Oklahoma; 2018. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/11244/299325.
Council of Science Editors:
Lucas J. FROM COOPERATION TO COMPETITION: HOW MICROBES AND INVERTEBRATES INTERACT IN A TROPICAL FOREST. [Doctoral Dissertation]. University of Oklahoma; 2018. Available from: http://hdl.handle.net/11244/299325

University of Saskatchewan
8.
Graves, Stephanie D.
Selenium uptake, trophic transfer, and toxicity in boreal lake ecosystems.
Degree: 2020, University of Saskatchewan
URL: http://hdl.handle.net/10388/13199
► Selenium (Se) is emerging as a contaminant of concern, particularly in mine and agriculture influenced areas of Canada and the United States. Due to the…
(more)
▼ Selenium (Se) is emerging as a contaminant of concern, particularly in mine and agriculture influenced areas of Canada and the United States. Due to the high site- and species-specificity of Se bioaccumulation, site-specific biodynamic modelling is the accepted approach to predict Se accumulation in aquatic systems, and fish tissue-based guidelines for the protection of aquatic life are preferred over water quality guidelines. To date, few studies have assessed Se bioaccumulation in cold-water systems, such as Canadian boreal forest lakes. These lakes, which comprise a large proportion of Canada’s freshwater, are also associated with several anthropogenic activities that can contribute to the excess release of Se to aquatic systems. Further, concern about excess Se has generally focused on the teratogenic effects on egg-laying vertebrates, with relatively little attention paid to aquatic invertebrates. The goal of this research was to improve the current understanding of Se biodynamics and toxicity in Canadian boreal lakes, with the ultimate goal of informing future ecological risk assessments of Se in Canada. Limnocorrals in two lakes located at the International Institute for Sustainable Development – Experimental Lakes Area (IISD-ELA) were used to conduct small scale whole-ecosystem experiments to study bioaccumulation and toxicity of Se. In 2017, Se was added as selenite to six limnocorrals (two treatment groups, each in triplicate) to achieve mean measured water Se concentrations of 1.0 and 8.9 µg/L and three limnocorrals were untreated controls (mean measured Se = 0.12 µg/L). Distribution coefficients (kds) ranged from 7,772 L/kg dry mass (dm) in the 8.9 µg/L treatment to 23,495 L/kg dm in the 0.12 µg/L treatment, and trophic transfer factors (TTFs) for benthic macroinvertebrates ranged from 0.49 for Gammaridae to 2.3 for Chironomidae. Selenium accumulated in fathead minnow ovaries to concentrations near or above the current British Columbia Ministry of the Environment and US Environmental Protection Agency criteria (11 and 15.1 µg/g dm for fish ovary/egg, respectively) in the 1.0 and 8.9 µg/L treatments. Chironomidae and Gammaridae densities and biomass were significantly lower in the 8.9 µg/L Se treatment relative to the 1.0 µg/L Se treatment and the control, and invertebrate diversity significantly declined in the 1.0 µg/L and 8.9 µg/L Se treatments relative to the control (0.12 µg/L Se group). In 2018, a gradient approach was used in which three limnocorrals were controls (0.08-0.09 µg Se/L), and mean measured concentrations in Se-treated limnocorrals were 0.4, 0.8, 1.6, 3.4, 5.6, and 7.9 µg/L. Total Se (TSe) bioaccumulation by organisms was generally non-linear over the gradient of water Se concentrations used, and taxonomic differences in TSe accumulation by algae (phytoplankton < periphyton) and invertebrates (Heptageniidae = Chironomidae > zooplankton) were observed. Zooplankton and benthic macroinvertebrate communities shifted according to Se exposure. Cladocera and Heptageniidae biomass and density…
Advisors/Committee Members: Janz, David, Weber, Lynn, Baulch, Helen, Liber, Karsten, Hecker, Markus, Palace, Vince.
Subjects/Keywords: selenium; food web; mesocosm; ecotoxicology; bioaccumulation
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Manager
APA (6th Edition):
Graves, S. D. (2020). Selenium uptake, trophic transfer, and toxicity in boreal lake ecosystems. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/13199
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Graves, Stephanie D. “Selenium uptake, trophic transfer, and toxicity in boreal lake ecosystems.” 2020. Thesis, University of Saskatchewan. Accessed April 11, 2021.
http://hdl.handle.net/10388/13199.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Graves, Stephanie D. “Selenium uptake, trophic transfer, and toxicity in boreal lake ecosystems.” 2020. Web. 11 Apr 2021.
Vancouver:
Graves SD. Selenium uptake, trophic transfer, and toxicity in boreal lake ecosystems. [Internet] [Thesis]. University of Saskatchewan; 2020. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/10388/13199.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Graves SD. Selenium uptake, trophic transfer, and toxicity in boreal lake ecosystems. [Thesis]. University of Saskatchewan; 2020. Available from: http://hdl.handle.net/10388/13199
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Canterbury
9.
Wootton, Katherine Lindsay.
Fitting species into the complexity-stability debate.
Degree: MS, Biological Sciences, 2015, University of Canterbury
URL: http://dx.doi.org/10.26021/5965
► Ecological communities – groups of interacting species – are subject to a variety of disturbances. Understanding responses to these disturbances is a primary goal of…
(more)
▼ Ecological communities – groups of interacting species – are subject to a variety of disturbances. Understanding responses to these disturbances is a primary goal of community ecology. The structural complexity of the community and the traits of the community’s constituent species are both known to have a significant impact on a community’s response to a disturbance. In this thesis, we investigated how these two scales – the community level and the species level – interactively affected community responses to both short and long term disturbances.
Our first hypothesis was that interaction strength would be weaker in species with many interactions when compared to species with fewer interactions. To test this hypothesis, we used simulated food webs and found that, in locally stable food webs, species with many interactions tended predominantly to have interactions with predators or with prey. While these many predator or prey interactions were weak, they tended to be balanced by a few interactions of the opposite type (with prey or predators) which were stronger than average. The structure of the network, where species had predominantly one type of interaction, was essential for this relationship between the number and strength of interactions to arise.
Our second study investigated how food webs of varying size and connectance respond to press and pulse disturbances. Many studies of food web stability only focus on the response to short term or “pulse” disturbances, however, as anthropogenic impacts on food webs increase, it is important to increase our understanding of food web responses to long term or “press” disturbances and determine whether they follow the same pattern as pulse disturbances. We found that more species rich and connected food webs were less stable to both types of disturbance and the more stable a food web was to a pulse disturbance, the more stable it was to a press disturbance as well. We also found that the traits – trophic level and number of interactions – of the disturbed species impacted a food web’s resistance to a press disturbance. Food webs were less resistant to the disturbance of species with many interactions or low trophic level than species with few interactions or high trophic level. The strength of species’ effects on stability was also moderated by the structural complexity of the food web.
Together the work that makes up this thesis suggests that, to understand the stability of food webs to any kind of disturbance, we
should consider both the structure of the network and the traits of
the species embedded within it. While we found that networks were
more vulnerable to disturbance of certain species than others, this
observation also depended on the structure and complexity of the
community they existed in. This has important implications for communities subject to disturbances, especially those disturbances which alter the way in which communities are structured and species interact.
Subjects/Keywords: species interactions; food web; stability; complexity; disturbance
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wootton, K. L. (2015). Fitting species into the complexity-stability debate. (Masters Thesis). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/5965
Chicago Manual of Style (16th Edition):
Wootton, Katherine Lindsay. “Fitting species into the complexity-stability debate.” 2015. Masters Thesis, University of Canterbury. Accessed April 11, 2021.
http://dx.doi.org/10.26021/5965.
MLA Handbook (7th Edition):
Wootton, Katherine Lindsay. “Fitting species into the complexity-stability debate.” 2015. Web. 11 Apr 2021.
Vancouver:
Wootton KL. Fitting species into the complexity-stability debate. [Internet] [Masters thesis]. University of Canterbury; 2015. [cited 2021 Apr 11].
Available from: http://dx.doi.org/10.26021/5965.
Council of Science Editors:
Wootton KL. Fitting species into the complexity-stability debate. [Masters Thesis]. University of Canterbury; 2015. Available from: http://dx.doi.org/10.26021/5965

University of Canterbury
10.
Peralta, Guadalupe.
Food webs from natural to production forests: composition, phylogeny and functioning.
Degree: PhD, Ecology, 2013, University of Canterbury
URL: http://dx.doi.org/10.26021/7220
► Habitat loss and fragmentation have been identified as the main drivers of biodiversity loss. These drivers increase the proportion of habitat edges and change the…
(more)
▼ Habitat loss and fragmentation have been identified as the main drivers of biodiversity loss. These drivers increase the proportion of habitat edges and change the configuration of landscapes. Habitat edges are known to affect ecological patterns and processes, however, is still unknown how these boundaries affect the assemblage of interactions among species within a community, and particularly its structure. Food webs depict not only the composition of the community, but also the feeding links, which represent a measure of energy flow. Therefore, they can inform about the relationships among community diversity, stability, and ecosystem functions.
This thesis explores the effects of habitat edges across native vs. managed forests on the food web of a tri-trophic system comprising plants, herbivores (Lepidoptera larvae) and predators (parasitoids). Particularly, it addresses three main objectives: 1) how food webs at habitat edges are assembled from the species and interactions present in the adjoining habitats; 2) how phylogenetic diversity and the coevolutionary signal among interacting species change across a habitat edge gradient; and 3) whether the mechanisms driving community-wide consumption rates and the ecosystem service of pest control are related to structural characteristics of the food webs.
The key findings of this thesis are that, despite the composition of species and interactions of native and managed habitats merging at their interface, food-web structure did not arise as a simple combination of its adjacent habitat webs, potentially due to differential responses of organisms to habitat edges. Moreover, beyond taxonomic composition, the phylogenetic diversity and signal of coevolution among interacting species also change between habitat types, even though this did not translate to changes in consumption rates. Consumption rates and their stability increased with complementarity and redundancy in resource-use among predators.
This reflects how environmental changes such as habitat fragmentation can have an effect beyond composition per se, affecting the assemblage of species interactions and even potentially interfering with natural evolutionary processes. Therefore, using interaction-network approaches for determining the impacts of changes may shed light on the underlying mechanisms driving such changes, and help to develop landscape management plans that reduce negative effects on species assemblages.
Subjects/Keywords: food web; fragmentation; habitat edges; phylogenetic diversity; coevolutionary signal; ecosystem functioning; food-web structure
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Peralta, G. (2013). Food webs from natural to production forests: composition, phylogeny and functioning. (Doctoral Dissertation). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/7220
Chicago Manual of Style (16th Edition):
Peralta, Guadalupe. “Food webs from natural to production forests: composition, phylogeny and functioning.” 2013. Doctoral Dissertation, University of Canterbury. Accessed April 11, 2021.
http://dx.doi.org/10.26021/7220.
MLA Handbook (7th Edition):
Peralta, Guadalupe. “Food webs from natural to production forests: composition, phylogeny and functioning.” 2013. Web. 11 Apr 2021.
Vancouver:
Peralta G. Food webs from natural to production forests: composition, phylogeny and functioning. [Internet] [Doctoral dissertation]. University of Canterbury; 2013. [cited 2021 Apr 11].
Available from: http://dx.doi.org/10.26021/7220.
Council of Science Editors:
Peralta G. Food webs from natural to production forests: composition, phylogeny and functioning. [Doctoral Dissertation]. University of Canterbury; 2013. Available from: http://dx.doi.org/10.26021/7220

University of Otago
11.
Hussein, Areege Hassan.
A web-based dietary assessment method for exploring iron bioavailability: developing a food list and pretesting
.
Degree: 2014, University of Otago
URL: http://hdl.handle.net/10523/4626
► Iron deficiency is the most common nutrient disorder worldwide. To assess intake in a population, food frequency questionnaires (FFQs) are commonly used as a low-burden,…
(more)
▼ Iron deficiency is the most common nutrient disorder worldwide. To assess intake in a population,
food frequency questionnaires (FFQs) are commonly used as a low-burden, cost-effective method of dietary assessment. However, most FFQs measure intake by day, and do not account for nutrient or
food component interactions when eaten as a meal. This is important for non-haem iron which has absorption modifiers (e.g., vitamin C and phytate) that affect its bioavailability. The
Web-Meal-Based Intake Assessment Tool (
Web-MBIAT) assesses iron intake by meal, potentially allowing for these interactions to be taken into account.
The first aim of this study was to generate a
food list for the
Web-MBIAT program that estimates the intake of iron and its absorption modifiers in premenopausal adult women (aged 19-50y) living in New Zealand. The second aim was to assess the usability of the
Web-MBIAT program from the perspective of the interviewer.
FOODfiles 2010 version 2.0 and literature on the phytate content of foods were used to generate two
food lists. Cut-offs were set using the literature or observing a natural break in the nutrient content of foods in FOODfiles. Cut-offs for the ‘main’
food list were: iron (≥2mg/100g); vitamin C (≥7mg /100g, except ≥10mg/100g for non-alcoholic beverages); meat, fish and poultry (≥30g/100g); and phytate (≥50mg/100g). The Adult Nutrition Survey 2008/09 was used to identify
food groups that contributed ≥4% to iron and ≥10% to vitamin C intake in the target population. Reasons for exclusion such as ‘similar item already in
food list’, were developed to limit the
food list length. Cut-offs for the ‘short’
food list were: iron (≥8mg/100g), vitamin C (≥80mg /100g) and phytate (≥750mg /100g).
Staff (who were Dietitians or Nutritionists) and graduate students were recruited by email from the Department of Human Nutrition, University of Otago, as interviewers to pretest the
Web-MBIAT and user’s manual. Interviewers conducted the FFQ with a standardized diet and were timed. Interviewers’ characteristics and audio recordings of their feedback were gathered, and a list of issues and suggestions were categorized for analysis.
The main iron
food list contained 420 items, (16% of the total number of foods in FOODfiles). The most common reason for inclusion and was meeting a specific
food component cut-off (97% of inclusions). The most common reason for exclusion was a ‘similar
food item already in
food list’ (47% of exclusions). The short
food list contained 24 items.
A total of 10 interviewers were recruited. In pretesting, most interviewers were positive about the
Web-MBIAT program and user’s manual. However, the main issues identified by both groups concerned the
Web-MBIAT’s ‘logic and navigation’ — particularly searching
food items — and the lack of colour in the user’s manual. Proposed modifications include removing case-sensitive searching of
food items, assessing supplement use, and having more prompts to guide the interviewer. The next step is to modify and validate the
Web-MBIAT…
Advisors/Committee Members: Heath, Anne-Louise (advisor).
Subjects/Keywords: Web-MBIAT;
Web-Meal Based Intake Assessment Tool;
Food frequency questionnaire;
iron;
pretesting
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hussein, A. H. (2014). A web-based dietary assessment method for exploring iron bioavailability: developing a food list and pretesting
. (Masters Thesis). University of Otago. Retrieved from http://hdl.handle.net/10523/4626
Chicago Manual of Style (16th Edition):
Hussein, Areege Hassan. “A web-based dietary assessment method for exploring iron bioavailability: developing a food list and pretesting
.” 2014. Masters Thesis, University of Otago. Accessed April 11, 2021.
http://hdl.handle.net/10523/4626.
MLA Handbook (7th Edition):
Hussein, Areege Hassan. “A web-based dietary assessment method for exploring iron bioavailability: developing a food list and pretesting
.” 2014. Web. 11 Apr 2021.
Vancouver:
Hussein AH. A web-based dietary assessment method for exploring iron bioavailability: developing a food list and pretesting
. [Internet] [Masters thesis]. University of Otago; 2014. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/10523/4626.
Council of Science Editors:
Hussein AH. A web-based dietary assessment method for exploring iron bioavailability: developing a food list and pretesting
. [Masters Thesis]. University of Otago; 2014. Available from: http://hdl.handle.net/10523/4626

NSYSU
12.
Chang, Chih-Hsien.
The biology of the snail Cerithium zonatum in an intertidal zone of Green Island.
Degree: Master, Marine Biology, 2010, NSYSU
URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0908110-093906
► Cerithium zonatum is a dominate species in an intertidal zone of Shi-Lang, Green Island. This study aimed to characterize the population dynamics, reproduction and trophic…
(more)
▼ Cerithium zonatum is a dominate species in an intertidal zone of Shi-Lang, Green Island. This study aimed to characterize the population dynamics, reproduction and trophic ecology of C. zonatum in this intertidal zone. Results indicated C. zonatum in rocky habitat had high density, high growth rate and small shell length. In seagrass bed it was low in population density and large in shell length. The reproductive season of C. zonatum was from spring to summer, with indirect development and short planktonic period. The C. zonatum was a primary consumer with δ13C values of -6.97 - -6.26‰ and δ15N values of 3.65 - 5.13‰. They fed on seagrass detritus and periphyton including microalgae and filamentous green algae. The major
food was seagrass detritus and filamentous green algae in the seagrass beds. In the rocky and sand habitats, the major
food was microalgae and filamentous green algae. The population dynamics and
food sources of C. zonatum were different among seagrass bed, rocky and sand habitats. In general, the C. zonatum was an opportunistic feeder with low mobility. And, the high population density and growth rate of C. zonatum in rocky habitat might result from abundant
food sources in the area.
Advisors/Committee Members: HinKiu Mok (chair), Li-Lian Liu (committee member), Hsing-Juh Lin (chair).
Subjects/Keywords: reproduction; population dynamics; isotope; Cerithium zonatum; food web
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chang, C. (2010). The biology of the snail Cerithium zonatum in an intertidal zone of Green Island. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0908110-093906
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Chang, Chih-Hsien. “The biology of the snail Cerithium zonatum in an intertidal zone of Green Island.” 2010. Thesis, NSYSU. Accessed April 11, 2021.
http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0908110-093906.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chang, Chih-Hsien. “The biology of the snail Cerithium zonatum in an intertidal zone of Green Island.” 2010. Web. 11 Apr 2021.
Vancouver:
Chang C. The biology of the snail Cerithium zonatum in an intertidal zone of Green Island. [Internet] [Thesis]. NSYSU; 2010. [cited 2021 Apr 11].
Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0908110-093906.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chang C. The biology of the snail Cerithium zonatum in an intertidal zone of Green Island. [Thesis]. NSYSU; 2010. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0908110-093906
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
13.
Merkley, Steven.
Resource Quantity and Quality in Cross-Ecosystem Food Web Subsidies.
Degree: Evolution, Ecology and Organismal Biology, 2016, University of California – Riverside
URL: http://www.escholarship.org/uc/item/6gc9g4df
► Prey moving from donor to recipient ecosystems (e.g. freshwater to terrestrial) are known as cross-ecosystem food web subsidies. These prey can affect the distribution and…
(more)
▼ Prey moving from donor to recipient ecosystems (e.g. freshwater to terrestrial) are known as cross-ecosystem food web subsidies. These prey can affect the distribution and abundance of subsidized predators. Most investigators have focused on how the quantity of prey (body size and biomass) affect predators, often assuming that resource quantity is an accurate proxy for resource quality. In the present dissertation, I used meta-analysis, lab, and field experiments to show the importance of measuring resource quality and how shifting quality of prey subsidies (insects) can influence a subsidized predator (Tetragnatha sp. spiders). Specifically, I define resource quality as a function of body nutrient content (%N) and carbon:nitrogen (C:N) ratio. In chapter two using data from 30 studies and ~250 effect sizes, I performed meta-analyses and demonstrated that increases in metrics of resource quantity (body size and dry weight) are not synonymous with increases in metrics of resource quality. In fact, there was a negative correlation between body phosphorus content (%P) and resource quantity. In chapter three, I tested how terrestrial spiders (Tetragnatha nitens) responded to different levels of prey quality by rearing them on three different prey: midges (Chironomus dilutus), mosquitoes (Culex quinquefasciatus), and fruit flies (Drosophila melanogaster). Mosquitoes were the lowest quality resource and lowered the nutrient content and stoichiometry of spider predators compared to the other treatments. Spiders fed on mosquitoes also suffered delays in growth and development due to being fed on the lower quality resource. Lastly, in chapter four, I tested how terrestrial spiders (Tetragnatha sp.) were affected by an aquatic nutrient enrichment in experimental field mesocosms. Abundance, body size (tibia + patella length (TPL) of first walking leg) (mm), biomass (mg), or nutrient stoichiometry (C:N ratio) of the subsidized Tetragnatha sp. spider did not differ significantly between enriched and non-enriched pools. However, significantly higher nitrogen content (% body N) was in Tetragnatha sp. spiders from the Santa Ana River inflow in a constructed treatment wetland compared to a site farther along this aquatic nutrient gradient during July 2015. Nutrient enrichment of the aquatic ecosystem due to anthropogenic runoff during a summer monsoon event may explain this pattern.
Subjects/Keywords: Ecology; Food web subsidies; Nutrient stoichiometry; Resource quality; Spiders; Stable Isotopes
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Merkley, S. (2016). Resource Quantity and Quality in Cross-Ecosystem Food Web Subsidies. (Thesis). University of California – Riverside. Retrieved from http://www.escholarship.org/uc/item/6gc9g4df
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Merkley, Steven. “Resource Quantity and Quality in Cross-Ecosystem Food Web Subsidies.” 2016. Thesis, University of California – Riverside. Accessed April 11, 2021.
http://www.escholarship.org/uc/item/6gc9g4df.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Merkley, Steven. “Resource Quantity and Quality in Cross-Ecosystem Food Web Subsidies.” 2016. Web. 11 Apr 2021.
Vancouver:
Merkley S. Resource Quantity and Quality in Cross-Ecosystem Food Web Subsidies. [Internet] [Thesis]. University of California – Riverside; 2016. [cited 2021 Apr 11].
Available from: http://www.escholarship.org/uc/item/6gc9g4df.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Merkley S. Resource Quantity and Quality in Cross-Ecosystem Food Web Subsidies. [Thesis]. University of California – Riverside; 2016. Available from: http://www.escholarship.org/uc/item/6gc9g4df
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Riverside
14.
Tobin, Jennifer Marie.
Selenium Partitioning and Food-Chain Transfer at the Salton Sea.
Degree: Environmental Sciences, 2011, University of California – Riverside
URL: http://www.escholarship.org/uc/item/40r8t899
► With the habitat at the Salton Sea, California, expected to decline to conditions unsuitable for wildlife as the Sea shrinks in coming years, efforts are…
(more)
▼ With the habitat at the Salton Sea, California, expected to decline to conditions unsuitable for wildlife as the Sea shrinks in coming years, efforts are being made to restore this valuable wildlife area. Current plans involve construction of a series of Species Conservation Habitat (SCH) ponds at the south end of the Sea to replace some of the habitat lost and evaluate options for further restoration. There is concern for the accumulation of selenium (Se) in the SCH ponds to levels potentially toxic to the birds they are meant to protect.In order to evaluate potential Se risk in the SCH ponds, this study employed a novel selenium modeling approach in which Se concentrations in food web organisms were linked to stable isotope data. Two freshwater lakes in Imperial County, CA, Finney Lake and Ramer Lake, were chosen as surrogates for the proposed SCH ponds. Organisms from the aquatic food webs of the two lakes were collected and analyzed for both Se concentration and carbon and nitrogen stable isotope composition. Se concentration was plotted against delta 15N for each lake to develop an empirical relationship between position in the food web and Se concentration that was then used to predict Se concentrations in piscivore and invertivore birds.Results provide direct evidence for the bioaccumulation of Se in freshwater habitats at the Salton Sea, but indicate that birds should be at little or no risk from Se toxicity in freshwater systems such as those at Finney and Ramer Lakes. Even though multiple food web components had Se concentrations above established toxicity thresholds, predicted bird concentrations were either below or only slightly above a widely used threshold for reduced hatchability.
Subjects/Keywords: Environmental science; Food web; Modeling; Salton Sea; Selenium
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tobin, J. M. (2011). Selenium Partitioning and Food-Chain Transfer at the Salton Sea. (Thesis). University of California – Riverside. Retrieved from http://www.escholarship.org/uc/item/40r8t899
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Tobin, Jennifer Marie. “Selenium Partitioning and Food-Chain Transfer at the Salton Sea.” 2011. Thesis, University of California – Riverside. Accessed April 11, 2021.
http://www.escholarship.org/uc/item/40r8t899.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tobin, Jennifer Marie. “Selenium Partitioning and Food-Chain Transfer at the Salton Sea.” 2011. Web. 11 Apr 2021.
Vancouver:
Tobin JM. Selenium Partitioning and Food-Chain Transfer at the Salton Sea. [Internet] [Thesis]. University of California – Riverside; 2011. [cited 2021 Apr 11].
Available from: http://www.escholarship.org/uc/item/40r8t899.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tobin JM. Selenium Partitioning and Food-Chain Transfer at the Salton Sea. [Thesis]. University of California – Riverside; 2011. Available from: http://www.escholarship.org/uc/item/40r8t899
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Tasmania
15.
Liao, JS.
Using Web 2.0 to enhance SME agri-food supply chain management: a Tasmanian study.
Degree: 2013, University of Tasmania
URL: https://eprints.utas.edu.au/17542/1/Whole-Liao%2C_Junheng_thesis.pdf
► This research project investigates the potential for Web 2.0 techniques (in this context, social media and websites using very accessible and scalable publishing techniques) to…
(more)
▼ This research project investigates the potential for Web 2.0 techniques (in this context, social media and websites using very accessible and scalable publishing techniques) to support and enhance agri-food supply chains within the Australian State of Tasmania. The research is based on three major areas of focus: agricultural and food supply chains (agri-food supply chains); small and medium size enterprises (SMEs) in these supply chains; and Web 2.0.
To achieve a representative outcome, both quantitative and qualitative data were gathered from a number of sub-sectors comprising seafood, dairy, livestock, fruit and vegetable.
The empirical research process made use of three data gathering stages: 10 key informant interviews to gather expert opinion prior to broader data collection, followed by a survey of 28 Tasmanian primary producers and, after refinement of the initial model, a validation focus group.
Since the majority of the interviewees had only limited familiarity with Web 2.0, a ‘typical’ Web 2.0 prototype was developed and presented during the survey interviews, allowing participants to trial the Web 2.0 application in a supply chain management (SCM) environment without risking their real businesses.
The results indicate the widespread popular view of the prevalence of Internet use. The majority of interviewees had also used some types of Web 2.0 technologies, although only a limited number of participants had used this sort of ICT at a sophisticated level – most interviewees used the Internet simply to obtain information, rather than actively engaging in content contribution. In particular, few of these SMEs had applied Web 2.0 to their agribusinesses, or to their supply chain activities. This situation is starting to change, however, as fragmentary Web 2.0 SCM applications begin to appear in many key areas of supply chain management including: procurement, processing and inventory management, marketing and sales, transport and customer service, as well as in all the sub-sectors investigated – some of them as a result of involvement in this project. One fisherman even developed his own iPhone app with record keeping and traceability functions for his fishing business.
The outcomes of this project suggest that applying Web 2.0 to SCM is not only driven by economic benefit, but also by lifestyle enhancement. Perceived effort expectancy, communication quality enhancement and social & other external factors also have significant effects on the adoption decision. Moreover, the degree of those perceptions also differs by gender (though, interestingly, it was the female participants who were most techno-savvy), age, customer types and technology experience – although the relatively small size of the sample means that some of these interactions will require further testing before their generalisability can be confirmed. Interestingly, the moderating effects of gender and age are diminishing as technology becomes more readily available and easier to use – and as Information Technology literacy becomes more…
Subjects/Keywords: Web 2.0; Agri-food; SMEs; supply chain management; Tasmania
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Liao, J. (2013). Using Web 2.0 to enhance SME agri-food supply chain management: a Tasmanian study. (Thesis). University of Tasmania. Retrieved from https://eprints.utas.edu.au/17542/1/Whole-Liao%2C_Junheng_thesis.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Liao, JS. “Using Web 2.0 to enhance SME agri-food supply chain management: a Tasmanian study.” 2013. Thesis, University of Tasmania. Accessed April 11, 2021.
https://eprints.utas.edu.au/17542/1/Whole-Liao%2C_Junheng_thesis.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Liao, JS. “Using Web 2.0 to enhance SME agri-food supply chain management: a Tasmanian study.” 2013. Web. 11 Apr 2021.
Vancouver:
Liao J. Using Web 2.0 to enhance SME agri-food supply chain management: a Tasmanian study. [Internet] [Thesis]. University of Tasmania; 2013. [cited 2021 Apr 11].
Available from: https://eprints.utas.edu.au/17542/1/Whole-Liao%2C_Junheng_thesis.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Liao J. Using Web 2.0 to enhance SME agri-food supply chain management: a Tasmanian study. [Thesis]. University of Tasmania; 2013. Available from: https://eprints.utas.edu.au/17542/1/Whole-Liao%2C_Junheng_thesis.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Cornell University
16.
Holeck, Kristen.
Investigating Lake Ontario’S Lower Food Web: Spatial Variation And Temporal Trends In Water Clarity, Phosphorus, Silica, Chlorophyll-A And Zooplankton.
Degree: M.S., Natural Resources, Natural Resources, 2016, Cornell University
URL: http://hdl.handle.net/1813/45254
Subjects/Keywords: Lake Ontario; oligotrophication; food web
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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Manager
APA (6th Edition):
Holeck, K. (2016). Investigating Lake Ontario’S Lower Food Web: Spatial Variation And Temporal Trends In Water Clarity, Phosphorus, Silica, Chlorophyll-A And Zooplankton. (Masters Thesis). Cornell University. Retrieved from http://hdl.handle.net/1813/45254
Chicago Manual of Style (16th Edition):
Holeck, Kristen. “Investigating Lake Ontario’S Lower Food Web: Spatial Variation And Temporal Trends In Water Clarity, Phosphorus, Silica, Chlorophyll-A And Zooplankton.” 2016. Masters Thesis, Cornell University. Accessed April 11, 2021.
http://hdl.handle.net/1813/45254.
MLA Handbook (7th Edition):
Holeck, Kristen. “Investigating Lake Ontario’S Lower Food Web: Spatial Variation And Temporal Trends In Water Clarity, Phosphorus, Silica, Chlorophyll-A And Zooplankton.” 2016. Web. 11 Apr 2021.
Vancouver:
Holeck K. Investigating Lake Ontario’S Lower Food Web: Spatial Variation And Temporal Trends In Water Clarity, Phosphorus, Silica, Chlorophyll-A And Zooplankton. [Internet] [Masters thesis]. Cornell University; 2016. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/1813/45254.
Council of Science Editors:
Holeck K. Investigating Lake Ontario’S Lower Food Web: Spatial Variation And Temporal Trends In Water Clarity, Phosphorus, Silica, Chlorophyll-A And Zooplankton. [Masters Thesis]. Cornell University; 2016. Available from: http://hdl.handle.net/1813/45254

Texas A&M University
17.
Zeug, Steven Christopher.
Demographic and trophic dynamics of fishes in relation to hydrologic variation in channel and floodplain habitats of the Brazos River, Texas.
Degree: PhD, Wildlife and Fisheries Sciences, 2009, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-1971
► Large rivers in North America have been subjected to a variety of hydrologic alterations that have negatively impacted aquatic fauna. These impacts have triggered restoration…
(more)
▼ Large rivers in North America have been subjected to a variety of hydrologic
alterations that have negatively impacted aquatic fauna. These impacts have triggered
restoration efforts, including management of flows, to restore or maintain ecological
integrity. Ecological data relevant to flow management and habitat restoration is scarce,
and conceptual models of ecosystem function have been widely applied to large rivers
despite a lack of quantitative evaluation of these models. Here, I examine demographic
and trophic dynamics of fishes with divergent life histories and trophic guilds in relation
to habitat heterogeneity and flow variability in a relatively unaltered floodplain system:
the Brazos River, Texas. Reproductive activity of fishes with three divergent life history
strategies was positively associated with long-term river hydrology, although species
with alternate strategies exploited different portions of the hydrograph (peak flow versus
increasing flow). Despite the positive association with hydrology, low-flow periods
were favorable for recruitment, and
food resources for larvae and juveniles were denser
during these periods. Some species used both oxbow and channel habitats during some
point in their life cycle, whereas other species appeared to be almost entirely restricted to
one habitat type. Terrestrial C3 macrophytes accounted for a significant fraction of the biomass of
most consumer species examined. Small-bodied species in oxbow lakes assimilated
large fractions of biomass from benthic algae, whereas this pattern was not observed in
the river channel. Frequent flow variations in the river channel may reduce algal
standing stocks, and significant contributions from autochthonous algal sources may
only occur during low-flow periods. Trophic positions of detritivores indicated that
terrestrial carbon sources were assimilated, for the most part, via invertebrates rather
than by direct consumption. My results indicate that current conceptual models are too
vague to provide accurate predictions for restoration strategies in rivers with variable
flow regimes. Flow and habitat management strategies that focus on reproducing key
features of historical fluvial dynamics are likely to be more successful than strategies
that focus on single indicator species or flow dynamics that differ from the historical
hydrograph.
Advisors/Committee Members: Winemiller, Kirk (advisor), Briske, David (committee member), Davis, Stephen (committee member), Fitzgerald, Lee (committee member).
Subjects/Keywords: reproduction; recruitment; isotopes; food web
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zeug, S. C. (2009). Demographic and trophic dynamics of fishes in relation to hydrologic variation in channel and floodplain habitats of the Brazos River, Texas. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1971
Chicago Manual of Style (16th Edition):
Zeug, Steven Christopher. “Demographic and trophic dynamics of fishes in relation to hydrologic variation in channel and floodplain habitats of the Brazos River, Texas.” 2009. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021.
http://hdl.handle.net/1969.1/ETD-TAMU-1971.
MLA Handbook (7th Edition):
Zeug, Steven Christopher. “Demographic and trophic dynamics of fishes in relation to hydrologic variation in channel and floodplain habitats of the Brazos River, Texas.” 2009. Web. 11 Apr 2021.
Vancouver:
Zeug SC. Demographic and trophic dynamics of fishes in relation to hydrologic variation in channel and floodplain habitats of the Brazos River, Texas. [Internet] [Doctoral dissertation]. Texas A&M University; 2009. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1971.
Council of Science Editors:
Zeug SC. Demographic and trophic dynamics of fishes in relation to hydrologic variation in channel and floodplain habitats of the Brazos River, Texas. [Doctoral Dissertation]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1971

University of Tasmania
18.
Jia, Z.
Surviving under the Antarctic sea ice : a study of the feeding ecology of Antarctic krill.
Degree: 2016, University of Tasmania
URL: https://eprints.utas.edu.au/23059/1/Jai_whole_thesis.pdf
► Antarctic sea ice covers approximately 4 million km2 during minimum extent in February/ March and grows to 19 million km2 during maximum extent in September/October.…
(more)
▼ Antarctic sea ice covers approximately 4 million km2 during minimum extent in February/
March and grows to 19 million km2 during maximum extent in September/October.
This sea ice zone harbours a wide diversity of biota and supports large populations
of unique Antarctic organisms. During the satellite era, Antarctic sea ice has shown
strong regional changes in its extent, duration, and the timing of the annual advance
and retreat. Improving our understanding of the relationships between sea ice and ice associated
animals will fill a crucial knowledge gap, which will facilitate the conservation
and management of the Southern Ocean ecosystems and resources.
This thesis compiles three studies focusing on the feeding ecology of Antarctic ice associated
zooplankton during the winter-spring transition. This work concentrates
on Antarctic krill (Euphausia superba), a key species with ecological and commercial
significance in Southern Ocean ecosystems.
Morphology defines an animal’s feeding capability. The morphological changes through
ontogeny of a species thus are not only important taxonomic information, but also crucial
for our understanding regarding its feeding ecology. In Chapter 2, I describe the
morphological changes of E. superba through its development from an egg to juvenile.
This is the first study since 1936 that fully describes the morphological features of
this species, in which I update the existent knowledge with details and high-resolution
photographs. Intermediate larval stages are identified and these morphological characteristics
are related to the overwintering survival strategies for this species.
The food that animals actually obtain from the environment can be investigated with
either gut content or biochemical analyses. To determine the dietary preferences and
trophic relationships of major zooplankton species (Chapter 3), I use stable isotope analyses
(13C/12C and 15N/14N) to compare samples collected from East Antarctic pack ice
zone during two winter-spring transitions (2007 and 2012). Interannual dietary differences
are determined for larval E. superba, suggesting feeding plasticity, which enables
this species to adapt to changing environmental conditions. Larval E. superba are primarily
herbivorous while utilising sea-ice biota, and consume a more heterotrophic diet
when feeding from the water column. In contrast, post-larval E. superba, and the omnivorous
krill Thysanoessa macrura consume a mixed diet from both the water column and
the sea ice. The pteropod Limacina helicina, small copepods in the genus Oithona spp.,
ostracods and amphipods rely heavily on sea-ice biota according to their carbon isotope
ratios. Large copepods and chaetognaths consume a water column-based diet during the
winter. The comparison of isotopic profiles between years suggests that ice-associated
zooplankton gain access to sea-ice biota more easily under warm and permeable ice than
under cold ice.
Our ability to construct food web models for sea-ice ecosystems are restricted by…
Subjects/Keywords: Antarctic krill; sea ice; zooplankton ecology; stable isotope; food web modelling
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Jia, Z. (2016). Surviving under the Antarctic sea ice : a study of the feeding ecology of Antarctic krill. (Thesis). University of Tasmania. Retrieved from https://eprints.utas.edu.au/23059/1/Jai_whole_thesis.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Jia, Z. “Surviving under the Antarctic sea ice : a study of the feeding ecology of Antarctic krill.” 2016. Thesis, University of Tasmania. Accessed April 11, 2021.
https://eprints.utas.edu.au/23059/1/Jai_whole_thesis.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Jia, Z. “Surviving under the Antarctic sea ice : a study of the feeding ecology of Antarctic krill.” 2016. Web. 11 Apr 2021.
Vancouver:
Jia Z. Surviving under the Antarctic sea ice : a study of the feeding ecology of Antarctic krill. [Internet] [Thesis]. University of Tasmania; 2016. [cited 2021 Apr 11].
Available from: https://eprints.utas.edu.au/23059/1/Jai_whole_thesis.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Jia Z. Surviving under the Antarctic sea ice : a study of the feeding ecology of Antarctic krill. [Thesis]. University of Tasmania; 2016. Available from: https://eprints.utas.edu.au/23059/1/Jai_whole_thesis.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – San Diego
19.
Hetherington, Elizabeth.
The interplay between trophic ecology, environmental variability, and an endangered marine species.
Degree: Biology, 2018, University of California – San Diego
URL: http://www.escholarship.org/uc/item/73j4n80z
► A grand challenge of the 21st century is to understand the response of ecosystems and populations of species to environmental variability and intensifying climate change.…
(more)
▼ A grand challenge of the 21st century is to understand the response of ecosystems and populations of species to environmental variability and intensifying climate change. My dissertation focuses on the potential for changing environmental conditions to influence marine food webs, foraging ecology, and ultimately population success of consumers. I combined biogeochemical tools (stable isotope analyses) of zooplankton and endangered leatherback turtles with measures of oceanography and environmental conditions to evaluate changes in foraging ecology and food web dynamics over time. My research specifically focuses on long-term trends in the foraging ecology and habitat use of Atlantic and Pacific leatherback turtles and how environmental variability in the Pacific may alter food web dynamics in a critical foraging area for a declining leatherback population. My first two chapters were focused on leatherback turtles, a cosmopolitan species with populations inhabiting tropical and temperate regions throughout the global ocean. In Chapter 1, I examined the trophic ecology of North Atlantic leatherbacks over an eighteen-year period to test the hypothesis that shifts in foraging ecology or environmental conditions in the North Atlantic have contributed to leatherback population recovery. In Chapter 2, I focused on a subgroup of the critically endangered Western Pacific leatherback population that forages in the California Current. Here, I addressed questions about their diet, habitat use, and the trophic structure of leatherback prey in the California Current Large Marine Ecosystem (CCLME). These two chapters allowed me to better understand whether the continuing decline of Pacific leatherbacks was related to dietary differences potentially driven by variability in environmental conditions between ocean basins as the North Atlantic population of turtles are steadily increasing. In Chapter 3, I investigated ecosystem responses to a multi-year, warm water anomaly (a marine heatwave and strong El Niño event) in the CCLME, which is a productive upwelling system that supports the biomass of many commercially and ecologically important species, including the leatherback population that Chapter 2 focused on. My findings illustrate mechanisms through which the amount of energy transferred to higher trophic level consumers is altered by environmental variability in the CCLME. In my first three chapters, I used stable isotope analyses, which can be a valuable tool for reconstructing patterns of trophic or foraging ecology over time. However, archived tissues that are used for analyses are often stored in chemical preservatives, which may affect their potential for use in isotope ecology. In Chapter 4, I conducted laboratory experiments to test the effects of common chemical preservatives on stable isotope values to better understand how we can best use preserved and archived tissues in future studies. My research provides insight into the trophic ecology and habitat use of an endangered marine consumer. Although I found no…
Subjects/Keywords: Ecology; El Niño; food web; leatherback turtle; stable isotope; trophic ecology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hetherington, E. (2018). The interplay between trophic ecology, environmental variability, and an endangered marine species. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/73j4n80z
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hetherington, Elizabeth. “The interplay between trophic ecology, environmental variability, and an endangered marine species.” 2018. Thesis, University of California – San Diego. Accessed April 11, 2021.
http://www.escholarship.org/uc/item/73j4n80z.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hetherington, Elizabeth. “The interplay between trophic ecology, environmental variability, and an endangered marine species.” 2018. Web. 11 Apr 2021.
Vancouver:
Hetherington E. The interplay between trophic ecology, environmental variability, and an endangered marine species. [Internet] [Thesis]. University of California – San Diego; 2018. [cited 2021 Apr 11].
Available from: http://www.escholarship.org/uc/item/73j4n80z.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hetherington E. The interplay between trophic ecology, environmental variability, and an endangered marine species. [Thesis]. University of California – San Diego; 2018. Available from: http://www.escholarship.org/uc/item/73j4n80z
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Humboldt State University
20.
Best, Michael.
Ecological role of the salamander Ensatina eschscholtzii: direct impacts on the arthropod assemblage and indirect influence on the carbon cycle in mixed hardwood/conifer forest in Northwestern California.
Degree: MS, Natural Resources: Wildlife, 2012, Humboldt State University
URL: http://hdl.handle.net/2148/1033
► Terrestrial salamanders are the most abundant vertebrate predators in northwestern California forests, fulfilling a vital role converting invertebrate to vertebrate biomass. The most common of…
(more)
▼ Terrestrial salamanders are the most abundant vertebrate predators in northwestern California forests, fulfilling a vital role converting invertebrate to vertebrate biomass. The most common of these salamanders in northwestern California is the salamander Ensatina (Ensatina eschsccholtzii). I examined the top-down effects of Ensatina on leaf litter invertebrates, and how these effects influence the relative amount of leaf litter retained for decomposition, thereby fostering the input of carbon and nutrients to the forest soil. The experiment ran during the wet season (November - May) of two years (2007-2009) in the Mattole watershed of northwest California. In Year One results revealed a top-down effect on multiple invertebrate taxa, resulting in a 13% difference in litter weight. The retention of more leaf litter on salamander plots was attributed to Ensatina???s selective removal of large invertebrate shedders (beetle and fly larva) and grazers (beetles, springtails, and earwigs), which also enabled small grazers (mites; barklice in year two) to become more numerous. Ensatina???s predation modified the composition of the invertebrate assemblage by shifting the densities of members of a key functional group (shredders) resulting in an overall increase in leaf litter retention. Results from year two indicated that these effects were affected by moisture availability, and that direct salamander impacts on invertebrates, and the related indirect effects on the capacity for forest floor leaf litter retention were diminished in the second, wetter year.
Advisors/Committee Members: Welsh, Hartwell H..
Subjects/Keywords: Salamanders; Ensatina; Carbon; Leaf litter; Food web; Trophic cascades; Invertebrates; Plethodontidae
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Best, M. (2012). Ecological role of the salamander Ensatina eschscholtzii: direct impacts on the arthropod assemblage and indirect influence on the carbon cycle in mixed hardwood/conifer forest in Northwestern California. (Masters Thesis). Humboldt State University. Retrieved from http://hdl.handle.net/2148/1033
Chicago Manual of Style (16th Edition):
Best, Michael. “Ecological role of the salamander Ensatina eschscholtzii: direct impacts on the arthropod assemblage and indirect influence on the carbon cycle in mixed hardwood/conifer forest in Northwestern California.” 2012. Masters Thesis, Humboldt State University. Accessed April 11, 2021.
http://hdl.handle.net/2148/1033.
MLA Handbook (7th Edition):
Best, Michael. “Ecological role of the salamander Ensatina eschscholtzii: direct impacts on the arthropod assemblage and indirect influence on the carbon cycle in mixed hardwood/conifer forest in Northwestern California.” 2012. Web. 11 Apr 2021.
Vancouver:
Best M. Ecological role of the salamander Ensatina eschscholtzii: direct impacts on the arthropod assemblage and indirect influence on the carbon cycle in mixed hardwood/conifer forest in Northwestern California. [Internet] [Masters thesis]. Humboldt State University; 2012. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/2148/1033.
Council of Science Editors:
Best M. Ecological role of the salamander Ensatina eschscholtzii: direct impacts on the arthropod assemblage and indirect influence on the carbon cycle in mixed hardwood/conifer forest in Northwestern California. [Masters Thesis]. Humboldt State University; 2012. Available from: http://hdl.handle.net/2148/1033

University of Waikato
21.
Binks, Nigel.
Assessing New Zealand's spider (Araneae) fauna, using DNA barcoding
.
Degree: 2018, University of Waikato
URL: http://hdl.handle.net/10289/11963
► The ability to accurately monitor biological diversity is the foundation to most ecological research. However, the morphological identification of spiders, as with many arthropod taxa,…
(more)
▼ The ability to accurately monitor biological diversity is the foundation to most ecological research. However, the morphological identification of spiders, as with many arthropod taxa, is often complicated by phenotypic plasticity and sexual dimorphism. New Zealand’s spider fauna is highly endemic (97% of known species), consisting of an estimated 2,000 species. Given such high diversity, it is critical to seek cost-effective measures of assessing species diversity and distributions, and for the identification of cryptic unidentified taxa.
The aim of my research was to determine whether the described spider fauna can be effectively delineated from unidentified taxa using DNA barcoding. Overall, I establish a molecular inventory for 100 described species and 71 additional unidentified species of spiders found in New Zealand. Using barcoding I determined there to be 59 native described species and classify 66 of the unidentified species as native, leaving 45 species which were recognised as having international distributions by taxonomic descriptions and/or from comparative DNA sequences from the Barcode of Life Datasystem (www.boldsystems.org). The repository of species presented here represent native species pertaining to 26 families and cosmopolitan species from 17 families of which species from the Araneidae, Linyphiidae and Theridiidae families are the most diversly represented in this study. This foundational inventory was used to assess the presence of spider species around the marginal habitats of 5 Waikato study lakes (Puketi, Rotoiti, Kohahuake, Waiwhakareke and Koraha), in relation to community assemblage variation across lakes, habitat (shoreline vs. pasture) and sampling method.
The combined morphological and molecular approach to identification used here has demonstrated community composition assessments of spiders are viable. Furthermore, the study of these community assemblages revealed a greater diversity of habitat specialists among shoreline samples from lakes Kohahuake, Koraha and Waiwhakareke where greater vegetative heterogeneity along the shoreline provides a greater range of niches for spiders to occupy. This compiled species inventory indicates that New Zealand’s diverse Araneae fauna has been infiltrated by species with international distributions. Further, not all species are easily recognisable due to dissimilarities in their morphological appearance, or because they remain to be genetically identified, and therefore the extent of non-native species infiltration into New Zealand ecosystems is unclear. This lack of knowledge highlights an important area for future biosurveillance work. Lake ecosystems were selected for this study because a variety of spider species prey upon adult aquatic invertebrates as they emerge from the aquatic realm and into the terrestrial.
Methods which provide complementary data for ranking lake ecosystems is a priority for biodiversity management in the Waikato region due to habitat fragmentation primarily associated with deforestation and subsequent…
Advisors/Committee Members: Collier, Kevin J (advisor), Hogg, Ian D (advisor).
Subjects/Keywords: Biodiversity;
spider;
conservation;
lakes;
waikato;
food-web;
community dynamics;
barcoding;
COI
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Binks, N. (2018). Assessing New Zealand's spider (Araneae) fauna, using DNA barcoding
. (Masters Thesis). University of Waikato. Retrieved from http://hdl.handle.net/10289/11963
Chicago Manual of Style (16th Edition):
Binks, Nigel. “Assessing New Zealand's spider (Araneae) fauna, using DNA barcoding
.” 2018. Masters Thesis, University of Waikato. Accessed April 11, 2021.
http://hdl.handle.net/10289/11963.
MLA Handbook (7th Edition):
Binks, Nigel. “Assessing New Zealand's spider (Araneae) fauna, using DNA barcoding
.” 2018. Web. 11 Apr 2021.
Vancouver:
Binks N. Assessing New Zealand's spider (Araneae) fauna, using DNA barcoding
. [Internet] [Masters thesis]. University of Waikato; 2018. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/10289/11963.
Council of Science Editors:
Binks N. Assessing New Zealand's spider (Araneae) fauna, using DNA barcoding
. [Masters Thesis]. University of Waikato; 2018. Available from: http://hdl.handle.net/10289/11963

Universidade Nova
22.
Ye, Zhelu.
A Web-Based geographical information system prototype on Portuguese traditional food products.
Degree: 2009, Universidade Nova
URL: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/2318
► Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies
Portuguese traditional food products use certification labels…
(more)
▼ Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies
Portuguese traditional food products use certification labels from EU quality schemes to distinguish from other food products. With the number of traditional food products increasing every year, how to manage the information more efficiently and how to spread the information to the public more clearly and interactively become the challenges. Considering the geographic distribution is one of the key features of the traditional food products, the web-based GIS is a potential system to manage and share the information. In this thesis, the prototype of web-based GIS is designed as three tiered software architecture comprising of web application, web service and spatial database. The prototype provides the possibility to integrate with the information from other sources. For the information managers, the prototype takes advantage of the web, open specifications and open source software. Therefore, it minimizes the barrier of the migration from original information system, and the information management is easy to be done in the web browser. For the public, the web map is easy to use and user-friendly. In the end, the potential improvement in the management web interface is discussed, and the further development such as introducing more roles into the system and having the usability test are pointed out.
Advisors/Committee Members: Neto, Miguel, Cabral, Pedro, Gould, Michael.
Subjects/Keywords: Open source software; Open specifications; Traditional food products; Web-based GIS
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
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APA (6th Edition):
Ye, Z. (2009). A Web-Based geographical information system prototype on Portuguese traditional food products. (Thesis). Universidade Nova. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/2318
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ye, Zhelu. “A Web-Based geographical information system prototype on Portuguese traditional food products.” 2009. Thesis, Universidade Nova. Accessed April 11, 2021.
http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/2318.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ye, Zhelu. “A Web-Based geographical information system prototype on Portuguese traditional food products.” 2009. Web. 11 Apr 2021.
Vancouver:
Ye Z. A Web-Based geographical information system prototype on Portuguese traditional food products. [Internet] [Thesis]. Universidade Nova; 2009. [cited 2021 Apr 11].
Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/2318.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ye Z. A Web-Based geographical information system prototype on Portuguese traditional food products. [Thesis]. Universidade Nova; 2009. Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/2318
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Illinois – Chicago
23.
Mores, Robin M.
Beyond the Binary Web: Using Real-Time PCR to Quantify the Structure of a Spider-Dominated Food Web.
Degree: 2016, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/20939
► Historically, food webs have been depicted as networks of binary interactions that show qualitative structure. Incorporating “weighted” data details interaction strengths and addresses a critique…
(more)
▼ Historically,
food webs have been depicted as networks of binary interactions that show qualitative structure. Incorporating “weighted” data details interaction strengths and addresses a critique in
food-
web theory – that binary webs are too simple. Additional simplifications of published
food webs include the aggregation of data across years/seasons and the aggregation of taxa into “functional groups”. This dissertation applies a molecular technique to the investigation of a
food web to address the questions: 1) Is
food web structure consistent across years and seasons? 2) How does foraging mode affect feeding interactions? 3) Are patterns of intra-guild predation (IGP) similar to interactions between predators and non-IGP prey? 4) Does examining interactions at a finer taxonomic resolution reveal divergent patterns in
food-
web structure? Real-time PCR was employed to examine predation within a model, spider-dominated
food web. Eleven spider families were examined for the gut-content DNA of eleven potential prey.
Food-
web structure was analyzed using connectance, compartmentalization, weighted connectance, interaction evenness and whole-
web specialization. The foraging mode of predators compared
web-building to cursorial spiders and examined specialization. The examination of IGP compared the structure of IGP
food webs to the structure of non-IGP webs. Examining interaction frequencies at a finer taxonomic resolution compared feeding patterns of families to those of genera with each family. Results showed the structure of the model
food web was consistent across years but not seasons. Spiders displayed differences according to foraging mode - cursorial spiders showed wider diet breadth compared to
web-builders. There were specialization differences between taxa, but this did not relate to foraging. Strong differences were seen seasonally when IGP interactions were compared to non-IGP interactions. Examining interaction frequencies at a finer taxonomic resolution revealed feeding patterns distinctly different from aggregating data to the family level. This dissertation demonstrates the importance of quantitative metrics in the examination of
food-
web structure. Temporal aggregation is sometimes sufficient to describe the structure of a
food web, but this is not necessarily true for finer degrees of resolution. Finally, this research establishes that the aggregation of taxa, even at the family level, does not adequately describe
food-
web structure.
Advisors/Committee Members: Wise, David H. (advisor), Minor, Emily (committee member), Gonzalez-Meler, Miquel (committee member), Sierwald, Petra (committee member), Harwood, James (committee member).
Subjects/Keywords: food web; real-time PCR; spiders; predation; forest floor; arthropod community
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mores, R. M. (2016). Beyond the Binary Web: Using Real-Time PCR to Quantify the Structure of a Spider-Dominated Food Web. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/20939
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Mores, Robin M. “Beyond the Binary Web: Using Real-Time PCR to Quantify the Structure of a Spider-Dominated Food Web.” 2016. Thesis, University of Illinois – Chicago. Accessed April 11, 2021.
http://hdl.handle.net/10027/20939.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mores, Robin M. “Beyond the Binary Web: Using Real-Time PCR to Quantify the Structure of a Spider-Dominated Food Web.” 2016. Web. 11 Apr 2021.
Vancouver:
Mores RM. Beyond the Binary Web: Using Real-Time PCR to Quantify the Structure of a Spider-Dominated Food Web. [Internet] [Thesis]. University of Illinois – Chicago; 2016. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/10027/20939.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mores RM. Beyond the Binary Web: Using Real-Time PCR to Quantify the Structure of a Spider-Dominated Food Web. [Thesis]. University of Illinois – Chicago; 2016. Available from: http://hdl.handle.net/10027/20939
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Tasmania
24.
Watson, A.
The impact of 170 years of flow regulation on processes and patterns in an eastern Tasmanian river system.
Degree: 2011, University of Tasmania
URL: https://eprints.utas.edu.au/12517/4/2Watson.pdf
► The flow regime of Tooms River, a tributary of the unregulated Macquarie River in eastern Tasmania, was modified in 1840 by a shallow dam in…
(more)
▼ The flow regime of Tooms River, a tributary of the unregulated Macquarie River in eastern Tasmania, was modified in 1840 by a shallow dam in its upper reaches, resulting in reversed seasonality of high and low flows: a classic, long-term example of a river subjected to “anti-drought”, but without the confounding thermal effects of impoundment stratification. I found surprisingly large differences between sites on this regulated branch and sites on the adjacent unregulated branch of the Macquarie, which persisted for 8 km downstream despite tributary inflows. This 2-year comparative study coincided with a prolonged supra-seasonal drought, which enabled examination of the effects of reduced stream flow on both regulated and unregulated examples of confined rivers in a naturally variable climatic regime. The regulated sites remained distinct from the unregulated sites, in terms of riparian litter fall, biofilm abundance and macro-invertebrate diversity.
This is one of very few studies of the long-term effects of flow regulation (e.g. see Kondolf and Batalla 2005; Sheldon and Thoms 2006b), and differs from the majority of regulated river studies in that the effects of regulation of Tooms River are not confounded by land use practises or thermal stratification of the reservoir. However, this impoundment is typical of small irrigation impoundments in Mediterranean and semi-arid climate zones. The ecological consequences of drought and “antidrought” in a region with a naturally variable flow regime may inform management of biodiversity in other regulated rivers in similar climate zones. Human population increases and climate change pressure on water supplies are likely to increase the demand for many more dams of this size and type of flow alteration (Benstead et al. 1999). The determination of the long-term effects of flow regulation is essential, so that future decisions on water allocations can be based on better knowledge of the impact on downstream ecosystem services.
Prolonged regulation of the flow regime of Tooms River has had major effects. Regulation has not only reversed the seasonality of flow, but has also dramatically reduced flow variability, resulting in contraction of the stream channel immediately downstream of the dam, and the establishment of mature eucalypts close to the channel, in contrast to the shrubby riparian vegetation maintained by the variable flow regime of the Macquarie River. The timing of allochthonous litter inputs to the benthos was altered, with peak litterfall delayed until irrigation demand fell at the end of summer. In addition, there was reduced lateral connectivity, with movement of leaf litter between the riparian zone and the benthos dependent on overland flow. As predicted by other studies, biofilms were more abundant in the regulated river, but the closed canopy immediately downstream of the dam did not suppress autochthonous productivity, against expectations. Chlorophyll a analyses indicated an autotrophic system, dominated by cyanobacteria and diatoms, in contrast to…
Subjects/Keywords: flow regulation; irrigation; drought; macroinvertebrates; biofilms; food web
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Watson, A. (2011). The impact of 170 years of flow regulation on processes and patterns in an eastern Tasmanian river system. (Thesis). University of Tasmania. Retrieved from https://eprints.utas.edu.au/12517/4/2Watson.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Watson, A. “The impact of 170 years of flow regulation on processes and patterns in an eastern Tasmanian river system.” 2011. Thesis, University of Tasmania. Accessed April 11, 2021.
https://eprints.utas.edu.au/12517/4/2Watson.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Watson, A. “The impact of 170 years of flow regulation on processes and patterns in an eastern Tasmanian river system.” 2011. Web. 11 Apr 2021.
Vancouver:
Watson A. The impact of 170 years of flow regulation on processes and patterns in an eastern Tasmanian river system. [Internet] [Thesis]. University of Tasmania; 2011. [cited 2021 Apr 11].
Available from: https://eprints.utas.edu.au/12517/4/2Watson.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Watson A. The impact of 170 years of flow regulation on processes and patterns in an eastern Tasmanian river system. [Thesis]. University of Tasmania; 2011. Available from: https://eprints.utas.edu.au/12517/4/2Watson.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
25.
Kennedy, Patrick.
The influence of the prey community on the growth and life history variation of aquatic apex predators in the Canadian Boreal Shield.
Degree: Biological Sciences, 2017, University of Manitoba
URL: http://hdl.handle.net/1993/32252
► Northern Pike (Esox lucius (Linnaeus, 1758)) and Lake Trout (Salvelinus namaycush (Walbaum, 1792)) are important apex predatory fish species that have ubiquitous distributions across Canada.…
(more)
▼ Northern Pike (Esox lucius (Linnaeus, 1758)) and Lake Trout (Salvelinus namaycush (Walbaum, 1792)) are important apex predatory fish species that have ubiquitous distributions across Canada. While these species have been well studied due to their economic value, there remains considerable uncertainty around the influence of prey community dynamics on their growth and life history variation across the Canadian Boreal Shield. I investigated how changes and differences in prey community dynamics of Boreal Shield lakes influence the growth and life history traits expressed by these apex predators to further understand how their life history strategies have evolved, as well as how their life history strategies might shift in the face of environmental change. Broad geographic comparisons among Northern Pike populations revealed evidence for a widespread generalist foraging strategy, one that takes advantage of the availability of offshore Cisco (Coregonus artedi (Lesueur, 1818)). Similar to the offshore predator Lake Trout, Northern Pike reached larger asymptotic lengths in lakes with greater abundances of Cisco. Northern Pike additionally exhibited slower early growth rates and lower mortality rates in lakes with greater abundances of Cisco. In the absence of larger offshore prey fish, Lake Trout growth appears to be strongly influenced by the availability of nearshore prey fish in Boreal Shield lakes. Following an increase in the productivity of cyprinids in an experimental lake, the early growth rates of Lake Trout increased significantly, with the greatest amount of growth occurring after a switch to piscivory at age 2. With a variety of stressors threatening the health and stability of aquatic ecosystems, this research provides vital information pertaining to the influence of prey community dynamics on the growth potential and life history variation of aquatic apex predators in the Canadian Boreal Shield.
Advisors/Committee Members: Rennie, Michael (Biological Sciences) (supervisor), Gillis, Darren (Biological Sciences).
Subjects/Keywords: Fisheries; Community Ecology; Life History; Food Web Dynamics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kennedy, P. (2017). The influence of the prey community on the growth and life history variation of aquatic apex predators in the Canadian Boreal Shield. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/32252
Chicago Manual of Style (16th Edition):
Kennedy, Patrick. “The influence of the prey community on the growth and life history variation of aquatic apex predators in the Canadian Boreal Shield.” 2017. Masters Thesis, University of Manitoba. Accessed April 11, 2021.
http://hdl.handle.net/1993/32252.
MLA Handbook (7th Edition):
Kennedy, Patrick. “The influence of the prey community on the growth and life history variation of aquatic apex predators in the Canadian Boreal Shield.” 2017. Web. 11 Apr 2021.
Vancouver:
Kennedy P. The influence of the prey community on the growth and life history variation of aquatic apex predators in the Canadian Boreal Shield. [Internet] [Masters thesis]. University of Manitoba; 2017. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/1993/32252.
Council of Science Editors:
Kennedy P. The influence of the prey community on the growth and life history variation of aquatic apex predators in the Canadian Boreal Shield. [Masters Thesis]. University of Manitoba; 2017. Available from: http://hdl.handle.net/1993/32252
26.
Selden, Rebecca.
The consequences of fishing-induced changes in predator size for predator-prey interactions.
Degree: 2015, University of California – eScholarship, University of California
URL: http://www.escholarship.org/uc/item/85c0h954
► Body size has long been recognized as a key driver of species interactions and of an individual’s role in the ecosystem. Body size determines the…
(more)
▼ Body size has long been recognized as a key driver of species interactions and of an individual’s role in the ecosystem. Body size determines the amount, species, and sizes of prey resources an individual can consume, as well as its own susceptibility to predators. Human harvest of predators can result in severe truncations in predator body size that can have cascading consequences on food webs. Where small and large individuals of the same species differ greatly in their diets, as is common in aquatic systems, the absence of large predators may functionally eliminate a key predator-prey linkage. Recently management agencies have begun to include size-based metrics as targets. As various harvest strategies differentially affect predator size and biomass, the research presented in this dissertation aims to understand the conditions under which truncations in predator size structure will result in additional loss of predator function than would be predicted from predator biomass alone, and where it will therefore be important to maintain predator size distributions. I specifically examine how the type of ontogenetic shift in diet (e.g. prey species or size class), and the shape of the diet switching function (e.g. gradual or abrupt) will affect the consequences of the loss of the largest predators, and the relative utility of various management strategies in maintaining predator function. In Chapter 1, I examined the tradeoffs between fishery yield and predator function in the ecosystem when preferentially fishing the largest predators. I found that fisheries that delay harvest until large predator sizes maximize fishery yield but that this virtually eliminates predation on focal prey eaten late in life history when diet shifts are abrupt and occur at or after the size at maturity. In this case, there is a clear tradeoff between fisheries and ecosystem objectives. Instead, where shifts in diet toward late prey are more gradual, targeting the largest predators can achieve a win-win by maximizing yield and achieving predation rates similar to that with other strategies that harvest predators earlier. As such, the optimal fishing strategy to achieve both single-species and ecosystem benefits depends strongly on the interaction between the fishery selectivity pattern and the changes in predator diet with size. In Chapter 2, I quantified the size-dependence of the predator-prey interaction between herbivorous sea urchins and one of their important predators in southern California kelp forests, California Sheephead. I further examined the consequences of changes in sheephead size and abundance in marine reserves at Catalina Island on size-specific urchin mortality in field predation trials. In my observations of predation of sheephead on urchins, sheephead smaller than 20cm TL do not eat urchins of any size. Thereafter, small sheephead only consumed small urchins, with larger sheephead sizes needed to successfully consume larger urchins, and the largest sheephead preferentially targeted the largest urchins. Inside…
Subjects/Keywords: Ecology; Conservation biology; body size; fishing; food web; predator
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Selden, R. (2015). The consequences of fishing-induced changes in predator size for predator-prey interactions. (Thesis). University of California – eScholarship, University of California. Retrieved from http://www.escholarship.org/uc/item/85c0h954
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Selden, Rebecca. “The consequences of fishing-induced changes in predator size for predator-prey interactions.” 2015. Thesis, University of California – eScholarship, University of California. Accessed April 11, 2021.
http://www.escholarship.org/uc/item/85c0h954.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Selden, Rebecca. “The consequences of fishing-induced changes in predator size for predator-prey interactions.” 2015. Web. 11 Apr 2021.
Vancouver:
Selden R. The consequences of fishing-induced changes in predator size for predator-prey interactions. [Internet] [Thesis]. University of California – eScholarship, University of California; 2015. [cited 2021 Apr 11].
Available from: http://www.escholarship.org/uc/item/85c0h954.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Selden R. The consequences of fishing-induced changes in predator size for predator-prey interactions. [Thesis]. University of California – eScholarship, University of California; 2015. Available from: http://www.escholarship.org/uc/item/85c0h954
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
27.
McLaughlin, John Peter.
The food web for the sand flats at Palmyra Atoll.
Degree: 2018, University of California – eScholarship, University of California
URL: http://www.escholarship.org/uc/item/45p5j103
► This dissertation describes and analyzes the Palmyra Atoll sand flat food web. This food web is unique in measuring the body sizes, densities, and feeding…
(more)
▼ This dissertation describes and analyzes the Palmyra Atoll sand flat food web. This food web is unique in measuring the body sizes, densities, and feeding links for all life stages of free-living and parasitic metazoans. Chapter 1 puts the research in context by reviewing the roles of parasites in marine food webs. Chapter 2 starts by describing the physical attributes (sediment particle size, water depth, temperature) of the 35 random sampling sites. It then lists the 22 sampling methods used to estimate the body size and abundance of 670 life stages comprising 275 species. The resulting free-living community contains represents 195 free-living species across 18 phyla, and 389 separate life stages. Chapter 2 then describes how parasites were measured from >2500 hosts collected and dissected to reveal a parasite community with 80 species across 9 phyla, and 281 separate life stages. Chapter 3 then uses stomach contents, field observations, literature, and natural history to estimate 24,575 trophic interactions, ontogenetic development and parasite transmission pathways among the 670 nodes in Chapter 2. Chapter 4 compares the Palmyra sand flat food web with the only published food web described in similar detail, the west coast estuary food web. In both systems, parasites make contributions to richness, abundance, and biomass comparable to free-living consumer groups, such as birds. Further, in both systems parasites dominate network structure in ways that free-living consumers cannot. These results suggest that parasites make general and important contributions to ecosystem structure. Our understanding of food webs is incomplete without them.
Subjects/Keywords: Ecology; Parasitology; Body size; Food web; Intertidal; Marine; Palmyra; Parasite
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
McLaughlin, J. P. (2018). The food web for the sand flats at Palmyra Atoll. (Thesis). University of California – eScholarship, University of California. Retrieved from http://www.escholarship.org/uc/item/45p5j103
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
McLaughlin, John Peter. “The food web for the sand flats at Palmyra Atoll.” 2018. Thesis, University of California – eScholarship, University of California. Accessed April 11, 2021.
http://www.escholarship.org/uc/item/45p5j103.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
McLaughlin, John Peter. “The food web for the sand flats at Palmyra Atoll.” 2018. Web. 11 Apr 2021.
Vancouver:
McLaughlin JP. The food web for the sand flats at Palmyra Atoll. [Internet] [Thesis]. University of California – eScholarship, University of California; 2018. [cited 2021 Apr 11].
Available from: http://www.escholarship.org/uc/item/45p5j103.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
McLaughlin JP. The food web for the sand flats at Palmyra Atoll. [Thesis]. University of California – eScholarship, University of California; 2018. Available from: http://www.escholarship.org/uc/item/45p5j103
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Plymouth
28.
Lauria, Valentina.
Impacts of climate change and fisheries on the Celtic Sea ecosystem.
Degree: PhD, 2012, University of Plymouth
URL: http://hdl.handle.net/10026.1/1166
► Climate change and fisheries have affected marine environments worldwide leading to impacts on ecosystem structure and functioning. However there is clear evidence of spatial variability…
(more)
▼ Climate change and fisheries have affected marine environments worldwide leading to impacts on ecosystem structure and functioning. However there is clear evidence of spatial variability in the response of these impacts both within and among marine ecosystems. Although several studies have tried to explain the effect of these impacts on marine food webs, it is unclear how they interact, and how they may affect marine ecosystems remains an important unanswered question. This suggests the urgent need for multiple-trophic level and ecosystem-based management approaches to account for both fisheries and climate change impacts at ocean basins across the globe. Marine apex predators, such as seabirds, are vulnerable to the effects of both climate and fishing impacts, and can be used as reliable and sensitive bio-indicators of the status of the marine ecosystem. The Celtic Sea ecosystem is a productive shelf region in the Northeast Atlantic. It is characterized by high fish and invertebrate biodiversity. In addition, internationally important numbers of seabirds, such as Northern gannet Morus bassanus (L.), Manx shearwater Puffinus puffinus (B.), Common guillemot Uria aalge (P.) and Black-legged kittiwake Rissa tridactyla (L.), breed along the Celtic Sea coasts. In recent years, fisheries from across Europe have intensively exploited the Celtic Sea, leading to changes in stock structure. Moreover, the increase in annual average Sea Surface Temperature by 0.67 °C over the past two decades has altered the composition of plankton communities. These impacts, independently and in tandem, are likely to have had dramatic effects upon the Celtic Sea food web emphasizing the need to enhance our understanding of this important marine ecosystem. In this thesis the effects of climate change and fisheries on the Celtic Sea pelagic food web are evaluated, in particular focussing on the response of seabird populations. This is in part because of recent declines in the breeding success of many seabird colonies in the northeast Atlantic, particularly around the North Sea. Long-term data across four trophic levels (phytoplankton, zooplankton, mid-trophic level fish and seabirds) and different modelling approaches are used to determine factors influencing seabird productivity at different geographical scales. First, I review the direct and indirect effects of climate change and fisheries upon marine ecosystems, as well as their impacts upon marine birds. Second, I use data collected during 1986-2007 from a single seabird colony, across four trophic levels, to investigate long-term direct and indirect climate effects. The results suggest only a weak climate signal in the Celtic Sea, and this is only evident between mid-trophic level fish and certain species of seabird. Third, a similar multi-trophic level approach across three nearby regions in the southwest UK (Irish Sea, Celtic Sea, and English Channel) reveal no evidence of a bottom-up signal during the period 1991-2007. These findings are in contrast with the nearby North Sea region, where…
Subjects/Keywords: 333.956; seabirds, climate change, fisheries, pelagic food web
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lauria, V. (2012). Impacts of climate change and fisheries on the Celtic Sea ecosystem. (Doctoral Dissertation). University of Plymouth. Retrieved from http://hdl.handle.net/10026.1/1166
Chicago Manual of Style (16th Edition):
Lauria, Valentina. “Impacts of climate change and fisheries on the Celtic Sea ecosystem.” 2012. Doctoral Dissertation, University of Plymouth. Accessed April 11, 2021.
http://hdl.handle.net/10026.1/1166.
MLA Handbook (7th Edition):
Lauria, Valentina. “Impacts of climate change and fisheries on the Celtic Sea ecosystem.” 2012. Web. 11 Apr 2021.
Vancouver:
Lauria V. Impacts of climate change and fisheries on the Celtic Sea ecosystem. [Internet] [Doctoral dissertation]. University of Plymouth; 2012. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/10026.1/1166.
Council of Science Editors:
Lauria V. Impacts of climate change and fisheries on the Celtic Sea ecosystem. [Doctoral Dissertation]. University of Plymouth; 2012. Available from: http://hdl.handle.net/10026.1/1166

University of Washington
29.
Moriarty, Pamela.
Quantifying Predator-Prey Interactions: Methods, Challenges, and Applications.
Degree: PhD, 2018, University of Washington
URL: http://hdl.handle.net/1773/42357
► Knowledge of predator-prey interactions is vital in many subfields of ecology, including food web ecology, behavioral ecology, and population ecology. Information on predator-prey interactions is…
(more)
▼ Knowledge of predator-prey interactions is vital in many subfields of ecology, including
food web ecology, behavioral ecology, and population ecology. Information on predator-prey interactions is obtained from a variety of sources, including stomach contents, biochemical tracers such as stable isotopes, fecal matter, and direct observation. These data sources are used to infer the predator’s diet and each presents analytical and interpretation challenges. In this dissertation, I pursue research to improve the analysis, interpretation, and application of varied data sources to study predator-prey interactions. My first chapter develops a mixture model to increase the accuracy and precision of diet estimates from stomach content data by addressing several challenges inherent to most stomach content datasets. I extend this model in my second chapter to address sample interdependence, which is a common issue due to sample collection methods. My third chapter addresses the challenges of applying stable isotope analysis to jellyfish due to their unique physiology and proposes a path forward to be able to use this data source effectively. My fourth chapter predicts the effect of hypoxia, a common environmental stressor, on energy flow from zooplankton to zooplanktivorous fish by merging multiple data sources in a Bayesian integrated assessment. Together, my dissertation research identifies and addresses some common challenges of analyzing predator-prey interactions.
Advisors/Committee Members: Essington, Timothy (advisor).
Subjects/Keywords: food web; mixture model; stomach contents; Ecology; Biostatistics; Fisheries
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APA ·
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APA (6th Edition):
Moriarty, P. (2018). Quantifying Predator-Prey Interactions: Methods, Challenges, and Applications. (Doctoral Dissertation). University of Washington. Retrieved from http://hdl.handle.net/1773/42357
Chicago Manual of Style (16th Edition):
Moriarty, Pamela. “Quantifying Predator-Prey Interactions: Methods, Challenges, and Applications.” 2018. Doctoral Dissertation, University of Washington. Accessed April 11, 2021.
http://hdl.handle.net/1773/42357.
MLA Handbook (7th Edition):
Moriarty, Pamela. “Quantifying Predator-Prey Interactions: Methods, Challenges, and Applications.” 2018. Web. 11 Apr 2021.
Vancouver:
Moriarty P. Quantifying Predator-Prey Interactions: Methods, Challenges, and Applications. [Internet] [Doctoral dissertation]. University of Washington; 2018. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/1773/42357.
Council of Science Editors:
Moriarty P. Quantifying Predator-Prey Interactions: Methods, Challenges, and Applications. [Doctoral Dissertation]. University of Washington; 2018. Available from: http://hdl.handle.net/1773/42357

Arizona State University
30.
Leinbach, Israel.
Free Water Fuels Intraguild Predation in a Riparian Food
Web.
Degree: Biology, 2015, Arizona State University
URL: http://repository.asu.edu/items/36499
► In desert riparian ecosystems, rivers provide free water but access to that water diminishes with distance producing a steep gradient in the relative importance of…
(more)
▼ In desert riparian ecosystems, rivers provide free
water but access to that water diminishes with distance producing a
steep gradient in the relative importance of water for growth and
reproduction of riparian animals and hence, their biodiversity.
Previous work suggests that water limited riparian predators eat
more prey to meet their water demand where free water is not
available. Here I explore the effect of water limitation on prey
selection and per capita interaction strengths between a predatory
spider ( Hogna antelucana) and two prey species occupying different
trophic levels using a controlled field experiment conducted in the
riparian forest of the San Pedro River, Cochise County, AZ. Lab
measurements of water and energy content revealed that intermediate
predators (smaller spiders in the genus Pardosa) had 100-fold
higher energy: water ratios than an alternate prey species more
basal in the food web (crickets in the genus Gryllus). Given this
observation, I hypothesized that water-stressed predatory wolf
spiders would select more water-laden crickets but switch to more
energy rich Pardosa when water stress was experimentally
eliminated. Additionally, I hypothesized that switching by quenched
Hogna to Pardosa would reduce predation by Pardosa on Gryllus
leading to increased abundance of the basal resource. Finally, I
hypothesized that water mediated switching and release of basal
prey would be stronger when male Hogna was the apex predator,
because female Hogna have higher energetic costs of reproduction
and hence, stronger energy limitation. Experimental water additions
caused both sexes of Hogna to consume significantly higher numbers
of Pardosa but this difference (between water and no-water
treatments) did not vary significantly between male and female
Hogna treatments. Similarly, strong negative interaction strengths
between Hogna and Pardosa led to release of the basal prey species
and positive interaction strengths of Hogna on Gryllus. Again
strong positive, indirect effects of Hogna on Gryllus did not
depend on the sex of the Hogna predator. However, water mediated
indirect effects of Hogna (either sex) on Gryllus were the
strongest for male Gryllus. These results suggest that water and
energy co-dominate foraging decisions by predators and that in
managing water-energy balance; predators can modify interaction
pathways, sex-ratios of prey populations and trophic
dynamics.
Subjects/Keywords: Ecology; Biology; food-web; IGP; Intraguild; predation; riparian; spider
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Leinbach, I. (2015). Free Water Fuels Intraguild Predation in a Riparian Food
Web. (Masters Thesis). Arizona State University. Retrieved from http://repository.asu.edu/items/36499
Chicago Manual of Style (16th Edition):
Leinbach, Israel. “Free Water Fuels Intraguild Predation in a Riparian Food
Web.” 2015. Masters Thesis, Arizona State University. Accessed April 11, 2021.
http://repository.asu.edu/items/36499.
MLA Handbook (7th Edition):
Leinbach, Israel. “Free Water Fuels Intraguild Predation in a Riparian Food
Web.” 2015. Web. 11 Apr 2021.
Vancouver:
Leinbach I. Free Water Fuels Intraguild Predation in a Riparian Food
Web. [Internet] [Masters thesis]. Arizona State University; 2015. [cited 2021 Apr 11].
Available from: http://repository.asu.edu/items/36499.
Council of Science Editors:
Leinbach I. Free Water Fuels Intraguild Predation in a Riparian Food
Web. [Masters Thesis]. Arizona State University; 2015. Available from: http://repository.asu.edu/items/36499
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