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Full-Text Articles in Life Sciences
Snowshoe Hare (Lepus Americanus) Abundance In Relation To Habitat And Predator Assemblage Across The Apostle Islands, Jarod Reibel
Snowshoe Hare (Lepus Americanus) Abundance In Relation To Habitat And Predator Assemblage Across The Apostle Islands, Jarod Reibel
Masters Theses
Snowshoe hares (Lepus americanus) are a climate sensitive species that have a southern range boundary moving northward. Snowshoe hares are found on the Apostle Islands, Wisconsin which are near their southern boundary and differ by island in vegetative and carnivore communities. The archipelago serves as a natural laboratory to assess how top-down and bottomup forces interact and impact snowshoe hare populations. The objectives of this study were to determine the influence of vegetative characteristics, specifically visual obstruction, and the presence of predators on snowshoe hare abundances across the Apostle Islands. We conducted fecal pellet surveys to estimate hare abundance, measured …
Territorial Behavior Of The Ozark Zigzag Salamander, Plethodon Angusticlavius, Altered By Mode Of Predator Cue And Sex Of Intruder, Sarah E. Heimbach
Territorial Behavior Of The Ozark Zigzag Salamander, Plethodon Angusticlavius, Altered By Mode Of Predator Cue And Sex Of Intruder, Sarah E. Heimbach
MSU Graduate Theses
Territorial defense in many species must be balanced with trade-offs in activities such as reproduction and predator avoidance. Adjusting behavior based on current assessments of predation risk and the cost of maintaining or gaining a territory is one way that individuals can balance trade-offs to maximize fitness. I conducted two experiments to determine how Ozark zigzag salamanders, Plethodon angusticlavius, adjust their territorial behavior-based predation risk. First, I tested whether male and female territorial intruders changed their competitive behavior according to whether predation risk is assessed via unimodal (chemical) or multimodal (chemical + physical) cues. Females and males responded differently to …
Comparing Feeding Accuracy Between High And Low Predation Trinidad Guppies, Lydia J. Bonnell
Comparing Feeding Accuracy Between High And Low Predation Trinidad Guppies, Lydia J. Bonnell
Honors College Theses
Efficient feeding accuracy could increase an organism’s survival. Although local adaptation in Trinidad guppies is common, the effects on accuracy are unknown. Guppies were wild caught in 2015 and 2017, filmed while capturing prey. Accuracy wasn’t different within samples but differed across samples, possibly due to the prey types used.
Eternal Enemies, Or Incidental Encounters? Structure And Patterns Of Interspecific Killing In Carnivora, Tor G. Bertin
Eternal Enemies, Or Incidental Encounters? Structure And Patterns Of Interspecific Killing In Carnivora, Tor G. Bertin
Theses and Dissertations
Lethal interactions between carnivorans (interspecific killing) may influence their population dynamics, behavior, and other important aspects of their ecology. In this study, I expand upon previous research on the broad-scale patterns of interspecific killing in Carnivora (Palomares & Caro 1999, Donadio & Buskirk 2006) with a greatly expanded dataset (inclusion of scat and stomach data and more intensive sampling of the literature), and suggest avenues for future research. While like previous studies, I found a positive effect of relative body size between killer species and killed species on the likelihood of forming a killing interaction, I failed to find evidence …
Ecosystem Functional Consequences Of Body Size Variation In An Apex Predator (Ambystoma Jeffersonianum), David Samuel Smith
Ecosystem Functional Consequences Of Body Size Variation In An Apex Predator (Ambystoma Jeffersonianum), David Samuel Smith
Online Theses and Dissertations
Biodiversity is often emphasized at the species level where each species is assigned a mean functional trait value. However, populations within a species, and individuals within a population, often exhibit considerable intraspecific functional variation. Therefore, instead of focusing on species’ mean trait values, we must incorporate intraspecific variation when considering species’ ecological roles and conservation values. The primary objective of this study was to determine the effects of variation in body size (a functional trait in many aquatic taxa) in an apex predator on ecosystem functioning. We sought to characterize trophic cascades initiated by larval populations of Ambystoma jeffersonianum that …