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You searched for subject:(Invertebrate Avoidance). Showing records 1 – 2 of 2 total matches.

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University of Saskatchewan

1. Voinorosky, Chelsea. The Effects of Targeted Triclopyr Application on Habitat Quality in Boreal Saskatchewan Transmission Rights-of-Way.

Degree: 2020, University of Saskatchewan

Vegetation management along transmission rights-of-way in remote northern forests across Canada is challenging. Mechanical removal of vegetation is often ineffective as many boreal species regenerate rapidly upon physical disturbance. Limited information on herbicide impacts in northern regions and on boreal vegetation makes communicating risks and benefits to local stakeholders and Indigenous communities difficult. Herbicides directly enter the ecosystem through deposition on vegetation and soils following application. Treated vegetation can be a vector of contamination to browsing herbivores, and herbicides can indirectly enter the soil ecosystem upon leaf abscission. Litter decomposition is critical to soil nutrient cycling and ultimately ecosystem health. The indirect effects of herbicides on habitat quality in boreal ecoregions remains poorly understood. Working in collaboration with SaskPower and the Lac La Ronge Indian Band, the influence of targeted applications of the herbicides, Garlon RTU and Garlon XRT (active ingredient triclopyr) were studied in northern Saskatchewan. Triclopyr drift and dissipation in foliage were assessed following a targeted low-volume foliar (Garlon XRT) or basal bark (Garlon RTU) application. Greater drift concentrations localized at the stem base were observed with basal bark treatments. These effects may be exacerbated with high stem density, especially in conjunction with sandy soil prevalent in northern Saskatchewan which increases the potential of herbicide mobility and off-target effects. Concentrations in foliage were higher following low-volume foliar applications but dissipated to 50% of initial concentrations within a week (DT50 = 5.7 days and DT90 = 34.6 days). A hazard quotient risk assessment for moose (Alces alces) and snowshoe hare (Lepus americanus) indicates browsing on triclopyr treated foliage with the residues detected in this study are unlikely to result in acute toxicity (extrapolated from concentrations that caused 50% mortality in rats and rabbits, respectively); however, long-term browsing may cause adverse chronic effects (extrapolated from the concentration with no observable effects in a two-generation reproduction rat study with a safety factor of 100). Basal bark application is ideal when stem density is lower and toxic effects for herbivores is of concern, and low-volume foliar applications are best suited in areas with higher stem density when off-target herbicide deposition is less acceptable. The indirect impacts of triclopyr on habitat quality were also examined through litter mass loss and quality (carbon:nitrogen ratios) as was the response of boreal invertebrates (Folsomia candida and Oppia nitens) in microcosms and avoidance tests. Higher concentrations of nitrogen (lower carbon:nitrogen) were observed in field treated foliage resulting from triclopyr repression of natural leaf senescence processes. Litter breakdown rates were not significantly different within a year of treatment despite nitrogen profile differences between field treated… Advisors/Committee Members: Stewart, Katherine, Liber, Karsten, Jardine, Timothy, Farenhorst, Annemieke.

Subjects/Keywords: Triclopyr; Ecotoxicity; Boreal; Basal Bark; Drift; Dissipation; Litter Breakdown; Invertebrate Avoidance; Habitat Quality

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

APA (6th Edition):

Voinorosky, C. (2020). The Effects of Targeted Triclopyr Application on Habitat Quality in Boreal Saskatchewan Transmission Rights-of-Way. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/13088

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):

Voinorosky, Chelsea. “The Effects of Targeted Triclopyr Application on Habitat Quality in Boreal Saskatchewan Transmission Rights-of-Way.” 2020. Thesis, University of Saskatchewan. Accessed October 23, 2020. http://hdl.handle.net/10388/13088.

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

MLA Handbook (7th Edition):

Voinorosky, Chelsea. “The Effects of Targeted Triclopyr Application on Habitat Quality in Boreal Saskatchewan Transmission Rights-of-Way.” 2020. Web. 23 Oct 2020.

Vancouver:

Voinorosky C. The Effects of Targeted Triclopyr Application on Habitat Quality in Boreal Saskatchewan Transmission Rights-of-Way. [Internet] [Thesis]. University of Saskatchewan; 2020. [cited 2020 Oct 23]. Available from: http://hdl.handle.net/10388/13088.

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

Council of Science Editors:

Voinorosky C. The Effects of Targeted Triclopyr Application on Habitat Quality in Boreal Saskatchewan Transmission Rights-of-Way. [Thesis]. University of Saskatchewan; 2020. Available from: http://hdl.handle.net/10388/13088

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


Mississippi State University

2. Kovalenko, Katya. INDIRECT EFFECTS OF INVASIVE SPECIES: COMMUNITY EFFECTS OF INVASIVE AQUATIC PLANT CONTROL AND DIRECT AND INDIRECT EFFECTS OF NON-NATIVE PEACOCK BASS.

Degree: PhD, Wildlife and Fisheries, 2009, Mississippi State University

Biological invasions are one of the main factors responsible for the imperiled status of freshwater ecosystems, but much remains to be learned about their indirect effects on native communities. The first part of this dissertation examines community effects of long-term efforts to selectively control invasive Eurasian watermilfoil. Results of the first study show that native plants immediately recolonized treated areas and habitat complexity was unaffected. Fish community was not influenced by invasive plant control. Macroinvertebrate communities were highly variable and part of their variability could be explained by plant community attributes. Both fish and macroinvertebrates used invasive watermilfoil, which emphasizes the need for timely restoration of native macrophytes to mitigate for lost habitat. Because fish and macroinvertebrates were more affected by complexity than other attributes of plant assemblage, reestablishment of habitat complexity appears to be a promising restoration strategy. The second study, which examined species interactions after watermilfoil control, found that fish feeding activity was not correlated with invasive plants or habitat complexity and that invasive macrophyte control did not affect characteristics of fish feeding investigated. The relationship between fish and macrophytes was further explored in the context of interactions between an invasive piscivore and its native prey. First, I examined the prey naiveté hypothesis with non-native peacock bass in Paraná River, Brazil. Prey responded to visual and chemical cues of peacock bass and displayed avoidance behaviors similar to those observed with a native predator, meaning that lack of recognition was not responsible for the observed vulnerability of native species to this introduced predator. After confirming lack of naiveté, I assessed direct and indirect effects of this non-native predator on native prey. Peacock bass had no indirect effects on its prey feeding activity. Macrophyte type did not affect indirect predator-prey interactions, whereas direct predator effects slightly decreased in the presence of aquatic vegetation. I discuss implications of these findings for native biodiversity and convene other potential explanations for the observed effects of peacock bass. Both projects contribute to our understanding of the relationship between aquatic plants and their animal communities and effects of invasive species in freshwater habitats. Advisors/Committee Members: Eric D. Dibble (chair), Gary N. Ervin (committee member), John D. Madsen (committee member), Todd E. Tietjen (committee member).

Subjects/Keywords: invasive macrophyte; Myriophyllum spicatum; structural complexity; fractal complexity; phytophilous macroinvertebrates; fish habitat; fish-invertebrate interactions; feeding selectivity; foraging activity; intimidation effects; predator-prey; non-native species; predator avoidance; prey naiveté; chemical cue; antipredator behavior; habitat restoration

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

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

APA (6th Edition):

Kovalenko, K. (2009). INDIRECT EFFECTS OF INVASIVE SPECIES: COMMUNITY EFFECTS OF INVASIVE AQUATIC PLANT CONTROL AND DIRECT AND INDIRECT EFFECTS OF NON-NATIVE PEACOCK BASS. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-06252009-203011/ ;

Chicago Manual of Style (16th Edition):

Kovalenko, Katya. “INDIRECT EFFECTS OF INVASIVE SPECIES: COMMUNITY EFFECTS OF INVASIVE AQUATIC PLANT CONTROL AND DIRECT AND INDIRECT EFFECTS OF NON-NATIVE PEACOCK BASS.” 2009. Doctoral Dissertation, Mississippi State University. Accessed October 23, 2020. http://sun.library.msstate.edu/ETD-db/theses/available/etd-06252009-203011/ ;.

MLA Handbook (7th Edition):

Kovalenko, Katya. “INDIRECT EFFECTS OF INVASIVE SPECIES: COMMUNITY EFFECTS OF INVASIVE AQUATIC PLANT CONTROL AND DIRECT AND INDIRECT EFFECTS OF NON-NATIVE PEACOCK BASS.” 2009. Web. 23 Oct 2020.

Vancouver:

Kovalenko K. INDIRECT EFFECTS OF INVASIVE SPECIES: COMMUNITY EFFECTS OF INVASIVE AQUATIC PLANT CONTROL AND DIRECT AND INDIRECT EFFECTS OF NON-NATIVE PEACOCK BASS. [Internet] [Doctoral dissertation]. Mississippi State University; 2009. [cited 2020 Oct 23]. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06252009-203011/ ;.

Council of Science Editors:

Kovalenko K. INDIRECT EFFECTS OF INVASIVE SPECIES: COMMUNITY EFFECTS OF INVASIVE AQUATIC PLANT CONTROL AND DIRECT AND INDIRECT EFFECTS OF NON-NATIVE PEACOCK BASS. [Doctoral Dissertation]. Mississippi State University; 2009. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06252009-203011/ ;

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