Behavior and Ethology Commons^™

Comparison Of Calcified Structures To Estimate Ages Of Northern Pike Esox Lucius In Various Lakes, Kaed Rauk

Journal of Earth and Life Science

Northern pike Esox lucius are a dominant predatory fish in many aquatic systems. They can have significant impacts on the ecosystems they inhabit and are also a popular game fish among anglers. However, northern pike are a difficult species to age accurately. This study aimed to compare calcified aging structures to identify trends and determine which structure provides the most accurate age estimates. A total of 119 northern pike were sampled, and multiple structures from each fish were independently aged by two readers. The coefficient of variation (CV) was calculated for each structure to assess precision. Sectioned sagittal otoliths exhibited …

Dietary Ecology Of Waterfowl Nest Predators In The Prairie Pothole Region: Evaluating Resource Use From Species To Individual Using Stable Isotope Analysis, Grace Barthelmess

EWU Masters Thesis Collection

Nest predation is a primary factor influencing waterfowl productivity in the Prairie Pothole Region (PPR) of North America. Although this system is intensely managed and studied, research has largely focused on how predators affect waterfowl populations, with comparatively little attention to how predators actually rely on waterfowl as a resource. Understanding predator feeding ecology is therefore critical for informing effective management strategies and interpreting the complexity of predator-prey interactions on this landscape. My objective overall was to elucidate the feeding ecology of nine focal predator species commonly associated with waterfowl nest predation in the Aspen Parkland Ecoregion of the PPR: …

Adapting To Uncertainty: Effects Of Environmental Instability On Zebrafish Behaviour, Britney Sekulovski

Theses and Dissertations (Comprehensive)

This thesis addresses how animals cope with unpredictability by testing how environmental stability changes the behaviour of zebrafish (Danio rerio) in two complementary experiments. In Experiment 1, fish lived for three months in either a Dynamic environment (water temperature, feeding times, habitat complexity, group size, and membership fluctuated) or a Stable environment (all factors constant). Across seven behavioural assays, measuring individual behavioural differences, collective movement, social memory, and information use, Dynamic condition fish were found to be more sensitive to social cues and more likely to conform to recent social information, independent of the quality of the information …

Nutritional Niche Separation Amongst Sympatric Threatened Lemurs: The Role Of Micronutrients In Food Selection And Implications For Physiological Health, Maire K. O'Malley

Graduate Research Theses & Dissertations

Madagascar’s biodiversity is heavily affected by anthropogenic change and consequently, conservation management plans need to reflect current research to protect biodiversity. Primate nutritional ecology offers valuable insights into ecology, evolution, health, habitat requirements, social behavior, and conservation management strategies. Macronutrients (fat, carbohydrates, and protein) provide consumers with energy whereas micronutrients (vitamins and minerals) are essential to metabolic processes but are frequently overlooked. This study provides a novel examination of dietary niche separation by comparing mineral consumption between three sympatric species differing in feeding strategies: 1) Grey Bamboo lemur (Hapalemur griseus), a bamboo specialist, 2) Diadema sifaka (Propithecus diadema), a folivore, …

Preventing Coccus Longulus Infestation, Nicholas Wellls

Honors College Theses

In the Armstrong greenhouse, the Coccus longulus scale insect is a prevalent problem on a specific species of Begonia known as Begonia ‘Richmondensis’. Inside the greenhouse there are several types of begonias with very similar characteristics to the Richmondensis begonia. However, none of these other begonias are infested by C. longulus, despite similar leaf thickness and environmental conditions such as humidity and light. This project examined whether differences in the chemical composition of the Begonia leaves can explain this pattern. Results were not statistically significant, but they showed that the chemicals had a noticeable impact on the scale, and …

Evidence Of Personality And Movement Syndromes In A Mobile Predator: How Individual Hunting Strategy Shapes Ecosystem Service Potential By Barn Owls (Tyto Furcata) In An Agroecosystem, Lauren M. Jackson

Cal Poly Humboldt theses and projects

Animal-mediated ecosystem services are delivered through the behavior of individuals, yet most studies evaluate service-providing species at the population level. We tested whether individual variation in plumage, behavior, and movement predicted hunting behavior and vineyard habitat use by adult male American barn owls (Tyto furcata) nesting in winegrape vineyards in Lodi, California, USA. We fitted GPS-accelerometer tags to 42 breeding males, quantified breast-plumage traits, measured neophobia using repeated novel object tests, and derived nightly movement metrics from GPS tracks and hidden Markov model-classified hunting locations. Several behavioral traits were repeatable, but movement traits showed the clearest repeatable individual …

A Sensory Ecology Of Fear: Moonlight-Mediated Predation Risk And Foraging Behavior In Neotropical Electric Fish, Chiu Lok Poon

Graduate Studies Theses and Dissertations 2026

Animals must forage to acquire energy for survival and reproduction, yet foraging exposes them to predators. This creates a trade-off between energy intake and safety, wherein the perception of predation risk alone can alter activity patterns. Within this trade-off, risk, energetic needs, and sensory adaptations vary, shifting the balance and favoring different foraging strategies. Using Neotropical electric fish as a study system, I investigated how foraging under predation risk is shaped across biological scales, including environmental dynamics, interspecific sensory differences, activity-timing mechanisms, and intraspecific variations. These nocturnal fish emit continuous electric signals to sense their environment, allowing non-invasive monitoring of …

Measuring Welfare Of Wild Tarantulas During Field Surveys Using Heart Rate, Tim Angelo Artiaga Lopez, Becky Hansis-O'Neill, Aimee Dunlap Phd

Undergraduate Research Symposium

Tarantulas (Theraposidae) are predatory arachnids that can help control populations of herbivorous arthropods. We have been monitoring populations of the Missouri brown tarantula (Aphonopelma hentzi) in Missouri glades for three seasons and have questions about their welfare during these surveys. Unlike mammals, arthropods are not extensively researched and there are only a few known facts about measuring their welfare. Managing stress for wild animals during field surveys is important for reducing the potential negative impacts of research. In mammals, increased heart rate is positively correlated with negative stress and eustress. Using the same logic, we hypothesized that heart rate could …

The Ecology Of Arthropod Rain In A Tropical Forest., Andrew Robert Seiler

Electronic Theses and Dissertations

Tropical forests are structured by complex vertical linkages and nutrient exchanges between canopy and understory habitats. These linkages include the downward flux of organisms, the movement of canopy fauna, and the recycling of nutrients through litter and organic matter deposition. This dissertation investigates arthropod rain and its role in connecting the canopy and forest floor processes in a lowland tropical forest in Panama. Chapter 2 quantifies “arthropod rain”, the fall of canopy arthropods into the understory. Using pan and pole traps, I measured the composition, abundance, and biomass of arthropods falling from the canopy and assessed environmental drivers of the …

Impacts Of Nutrient Addition And Disturbance On Coastal Dune Arthropod Communities And Trophic Interactions, Kayla Beitzel

Graduate Theses and Dissertations (2019 - present)

Coastal dune ecosystems face ongoing threats from human-mediated disturbance and altered resource availability. Because these dunes provide critical habitat for many organisms, including shorebirds, beach mice, and arthropods, changes in disturbance regimes or resource availability can impact plant communities and higher trophic levels by altering plant richness and productivity, which in turn influence arthropod abundance and diversity. To examine how disturbance and nutrient addition affect arthropod communities, we established twenty 5×5 m plots on Dauphin Island, crossing mechanical disturbance with a 10 g m⁻² addition of nitrogen, phosphorus, and potassium, replicated across five experimental blocks. Arthropods were sampled using three …

Spotted Seal Coastal Haul Out Behavior In Arctic Alaska, Maeghan Connor

Biological Sciences

Hauling out - the act of exiting the water to rest, molt, breed, and pup on solid surfaces - is a key behavior of pinnipeds worldwide. Unlike other ice seals (i.e., ice-associated phocid species), spotted seals (Phoca largha) in Alaska frequently use terrestrial substrates to haul out during the summer and fall open-water period in the Chukchi and Beaufort Seas. Despite being a core aspect of spotted seal ecology, their terrestrial haul out behavior remains understudied. To address this, we analyzed data collected from 2020 - 2022 near two known haul out sites in Dease Inlet, Alaska, including time-lapse camera …

[Chu] Modelling The Effect Of Disturbed Blood-Feeding On Mosquito-Borne Disease Transmission, Kyle Dahlin, Michael Robert, Lauren Childs

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Phylogenetic Comparative Vocal Evolution, Casper W. Buchanan

Master's Theses

Vocal learning is a trait unique to humans, bats, cetaceans, primates, and birds (Jarvis & Nottebohm, 1997; McComb & Semple, 2005; Wilbrecht & Nottebohm, 2003). Although there has been extensive research on vocal learning in songbirds, parrots are an even closer proxy to human learning, as they are social, intelligent, and lifelong learners, with some having repertoires of over 300 sounds (Benedict et al., 2022; Péron et al., 2011; Thomsen et al., 2019; Toft & Wright, 2015). Elevated vocal learning can be attributed to the need for parrots to have strong communication skills through the sharing of information over foraging, …

Notes On Reproduction, Seasonality, And Roost Sites For Silver-Haired Bats (Lasionycteris Noctivagans) In Western Nebraska, Joseph W. Paysen, Dawson V. Kosmicki, Keith Geluso

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Silver-haired Bats (Lasionycteris noctivagans) are a migratory species found throughout the United States, southern Canada, and northern Mexico. Throughout their range, Silver-haired Bats roost in various tree species, generally within decaying features like cavities and exfoliated bark. Herein we report on additional reproductive and seasonal data as well as the first data on trees used as roost sites by Silver-haired Bats in Nebraska. We captured individuals along a small tributary of the North Platte River at Ash Hollow State Historical Park, Garden County, Nebraska, and tracked bats to their roosts. At this location, we documented lactation on 17 …

Cephalopod Consciousness: Asking The Right Questions, Gordon Burghardt

Animal Sentience

Jennifer Mather has provided a comprehensive and fascinating overview of the various cognitive accomplishments of cephalopods and their sensory, behavioral, and neurophysiological attributes. The advances in our understanding of a clade that has been separated from vertebrate evolution by well over half a billion years is a testament to advances in both methodology and the questions we now feel free to address. Mather embeds her review in the issue of consciousness, which is certainly a perennial issue in mental evolution, going back to Romanes and earlier. I argue that the term “consciousness” has such a checkered history and is used …

Using Livestreaming Technology To Answer Novel Questions About The Behavior And Physiological Ecology Of The Prairie Rattlesnake (Crotalus Viridis), Max C. Roberts

Master's Theses

Recent advances in remote monitoring technology are opening up new opportunities for developing innovative natural history and biological research methodologies. In particular, the emergence of livestreaming camera technology has made recording remote video of wild and secretive animals much easier and made it possible to collect data at extremely fine temporal resolutions. In 2024, Project RattleCam launched a livestreaming camera at a Prairie Rattlesnake (Crotalus viridis) den in Colorado. The goal of this work was to study Prairie Rattlesnake behavior 24-7 throughout the species’ active season with minimal human disturbance. Additionally, I used this system to study the …

Investigating Rattlesnake Social Networks And Improving Their Public Image Through Unobtrusive Technologies And Community Science, Owen M. Bachhuber

Master's Theses

While technology is often blamed for humans’ increasing disconnect with nature, it can also serve as a tool to facilitate empathy and conservation action for wildlife. Snakes are among the most feared animals on the planet, though their understudied social interactions provide opportunities to make scientific discoveries and change public perceptions. Project RattleCam was founded as a camera trap project in 2021 and launched the first off-grid livestream on a den of wild Prairie Rattlesnakes (Crotalus viridis) in 2024. Both camera types captured hundreds of Prairie Rattlesnakes gathering in the summer as they prepared to give birth to pups before …

Coyote (Canis Latrans) And Non-Target Wildlife Responses To Livestock Guardian Dogs At Sheep Grazing Sites On The California Central Coast, Tricia T. Nguyen

Master's Theses

Livestock depredation is one of the oldest and most widespread forms of human-wildlife conflict. The coyote (Canis latrans), a midsized canid, represents a significant proportion of domestic sheep depredations in the United States, costing livestock producers an estimated 24.6 million dollars annually. Management strategies for coyote-sheep depredation vary widely in their effectiveness and in their level of public support. Identifying appropriate strategies for farms, ranches, and other sheep grazing sites remains a pressing need due to the potentially negative consequences for surrounding ecosystems and socioeconomic outcomes for sheep producers. The livestock guardian dog (LGD) is a nonlethal control …

Investigating The Impact Of Psychoactive Plant Alkaloids On Bumblebee Behavior, Skylar Mathieson

Electronic Theses and Dissertations

The relationship between plants and their pollinators is often framed as a food-for-service exchange in which plants provide pollinators with nutrients in exchange for transport of their gametes. However, in addition to essential nutrients, many floral rewards (nectar, pollen) also contain defensive toxins such as alkaloids, with largely unexplored consequences for plant-pollinator interactions. I investigated how three psychoactive and addictive plant alkaloids — caffeine, nicotine, and morphine — affect foraging behavior in generalist bumblebees (Bombus impatiens) using robotic flowers. Each of these chemicals affected pollinator foraging behavior, influencing the number and duration of their visits to flowers in …

Drivers And Consequences Of Changes In Nectar Microbiome Composition Across Spatial And Biological Scales, Daniel A. Barker

Electronic Theses and Dissertations

Microbial communities inhabiting floral nectar, known as the nectar microbiome, are important mediators of plant-pollinator interactions. However, the ecological and environmental factors that shape the composition of these microbial communities remain poorly understood. While previous studies have examined the effects of a few microbial groups, typically independent of one another, on one plant or pollinator species, this dissertation takes a wide-scale approach to explore how abiotic conditions and biotic interaction’s structure microbial communities within floral nectar. Furthermore, I also quantify how variation in microbial richness and identity influences pollinator behavior and plant reproductive success.

This dissertation shows that microbial abundance …