Life Sciences Commons^™

Supply Is Not Limulus: Research Review Of Horseshoe Crab Conservation In The Face Of Intense Pharmaceutical Demand, Zoya Galeev

University Honors Theses

Horseshoe crabs are being used by the pharmaceutical industry to conduct endotoxin tests using LAL derived from the organism’s blood to ensure safe medical practice. Their annual collection and bleeding, while not always leading to mortality, affects horseshoe crab behavior and health. This research seeks to understand how the American horseshoe crab, L. polyphemus, is being used by pharmaceutical agencies and the implications that their harvesting has on the industry and the conservation of the species. Studies were collected from the past decade across two databases, Web of Science (WOS) and PubMed, to assess present conservation techniques to reduce …

How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige

University Honors Theses

Oregon is home to two native freshwater turtle species: the northwestern pond turtle and the western painted turtle. Both turtles are Oregon conservation strategy species with a status rating of sensitive, indicating declining populations. Oregon’s decline in these turtle’s populations is thought to be predominantly due to loss and degradation of habitat that results from development and urbanization. Beavers’ ability to dam streams and create ponds may be creating habitat usable by turtles, but the relationship is under-studied. This study assessed water temperature, basking habitat, and overall turtle habitat suitability at beaver-dammed and control ponds in Portland, Oregon. Average basking …

Genetic Considerations For The Conservation Of The Red Junglefowl, Courtney Lee Mcpheron

University Honors Theses

The undomesticated wild populations of our domestic species deserve heightened consideration when it comes to their conservation. Not only do they carry significant socio-cultural and economic roles, but they offer an exceptionally unique case study for population genetics. The red junglefowl (Gallus gallus) of southern and south-eastern Asia is considered to be the living ancestor and progenitor of the domestic chicken. This literature review examines how published research has evaluated its genetic relationship with the chicken and implications for its conservation. A special emphasis is given to the threat of genetic introgression with domestic and feral chicken populations …

Management Plan For The Western Painted Turtle At The Sandy River Delta In Troutdale, Oregon, Emma Scott

Environmental Science and Management Professional Master's Project Reports

This management plan has been prepared for the Lower Columbia Estuary Partnership and is intended to provide guidance for the improvement and protection of western painted turtle (Chrysemys picta bellii) habitat at the Sandy River Delta in Troutdale, Oregon. The Sandy River Delta is a 1500-acre natural area situated where the Columbia and Sandy Rivers meet. Its dynamic floodplain habitat supports a diverse assemblage of species, including the western painted turtle, an Oregon Conservation Strategy Species. A small, unknown number of western painted turtles utilize the wetland habitats of the Sandy River Delta, and the frequency in observations …

A Review Of Current Sea Cucumber And Apostichopus Californicus Knowledge And A Proposal For Future Research And Fishery Management, Lily Haug

University Honors Theses

The sea cucumber species Apostichopus californicus is fished in the Pacific Northwest region of North America and has the potential to be an economically beneficial fisheries species. An understanding of their population levels must be present to sustainably regulate their harvest. Current fisheries in North America vary in their methodology and level of regulation. The current regulations are presented and their strengths and shortfalls are described. This review gathers research done on tropical sea cucumber species and presents that knowledge alongside that regarding Apostichopus californicus to suggest future research and fishery management strategies. A. californicus takes four years to sexually …

A Review Of Animal Welfare And Current Enrichment Methods For Captive Marine Mammals, Ashleigh I. Richardson

University Honors Theses

Animal care and conservation facilities such as zoos, aquaria, and marine mammal parks often utilize a variety of enrichments to deter stereotypic behaviors and improve overall animal welfare. Facilities that go through the intense accreditation process of one or more accreditation organizations must uphold the animal care standards and education requirements that these organizations call for. These care standards typically include regulations regarding animal training and enrichment, though the extent to which these regulations go into detail often vary from species to species and between organizations. The goal of this review was to assess the current standard of animal enrichment …

A Multi-Species Study On Several Types Of Visitor Effects On The Behavior And Physiology Of Animals At The Oregon Zoo, Laurel Berylline Fink

Dissertations and Theses

The visitor effect on zoo animals is one of the expanding research topics in zoo animal research. As visitors are a mandatory feature of zoological institutions, understanding their effects on zoo animals is imperative for maximizing zoo animal welfare. Zoo animals are subject to many anthropogenic influences: visual, olfactory, and audible, for example. This dissertation investigates several of the effects of visitor presence and its relative influence on six mammalian species: cheetahs (Acinonyx jubatus), African painted dogs (Lycaon pictus), Asian elephants (Elephas maximus indicus & Elephas maximus borneensis), giraffes (Giraffa camelopardalis reticulata & …

A Literary Examination Of The Efficacy Of Zoological Conservation In The United States Versus Foreign Efforts, Madeleine M. Lecorre

University Honors Theses

Falling into the top four threats to biodiversity, human activity is impacting species around the globe like never before. Zoological conservation of threatened species aids in the support and reestablishment of these dwindling populations. The examination of conservation work done in the U.S compared to foreign efforts provides insight into strengths, reveals weaknesses, and will help us better serve threatened species around the world. The status of conservation in the U.S. as well as foreign efforts were assessed through literary review of published reports from accredited organizations. As zoologic conservation aims to conserve threatened species, it is also important to …

A Survey Of The Solitary Native Bees Of The Leach Botanical Garden, And Their Floral Associations, Joshua Page

Biology Undergraduate Departmental Honors Theses

Solitary native bees are known to be diverse, but are not well studied in Oregon. In order to identify the bee genera present in the Leach Botanical Garden, and their floral usage, a survey was conducted over 2020 and 2021. Biweekly sampling was used to collect bees on flowers, in order to obtain floral usage data. Bees were identified to genus with published taxonomic keys. In total, 19 genera of bees were found. Bee abundance fit a normal distribution, and peaked in July. Ceratina and Lasioglossum were a significant proportion of the population, and were present in the garden from …

Examination Of Exhaustion In Larval Pacific Lamprey (Entosphenus Tridentatus) Through Variations Of Temperature, Flow, And Cover, Jessica Falcon

University Honors Theses

Pacific lampreys (Entosphenus tridentatus) are culturally and ecologically valuable throughout the western coast of North America. The larval (ammocoete) stage of the Pacific lamprey spends three to eight years burrowed in the sediment as a filter feeder, and is an essential contributor to many of the Northwest’s freshwater ecosystems. Larval lamprey may be vulnerable to warming waters caused by climate change as well as seasonal dredging and salvaging events that dislodge lamprey from sediment, as they prefer cooler water and are relatively poor swimmers in comparison to other fish such as salmon. In this study, we observed how …

Human Impact On Pacific Harbor Seals In Urban Southern Puget Sound, Washington, Vicky Gomez

University Honors Theses

This research proposal aims to highlight the quantitative and qualitative impact of human disturbances Pacific Harbor Seals (Phocca vitulina) are experiencing in urban southern Puget Sound, Washington and how the data collected can educate the community to protect and conserve a healthy population of Harbor Seals. Urbanization and areas utilized by harbor seals within urban settings prompted data collection from four nearby sites: site A, Carylon Beach, includes pedestrian and boat disturbances, site B, Tacoma Tidal Flats, only experience boat disturbances, site C, West Bay Marina, experiences motorized and non-motorized boat disturbances and site D, Gertrude Island, is …

Our Peer The Pigeon: Impacts Of The Covid-19 "Anthropause" On Psu Campus Urban Foragers, Audrey Douglass

University Honors Theses

The 2020 COVID Pandemic presented a paradigm shift dubbed, by some scholars, the 'Anthropause', an ecological epoch in which humans faded from the public sphere. As was the case for many urban species that depend on the foraging of food waste, this meant a fundamental disruption to their food systems and to the entire urban eco-web. The PSU Campus Park Blocks presents a unique opportunity to observe animal behavior, while also a succinct microcosm to study food waste flow changes, and compare species layout to other urban parks in the METRO area. Decreased food waste output from proximal …

Density Of Free-Roaming Cats Related To Feeding Stations On Hayden Island, Oregon, Olivia Helback, Joe Liebezeit

University Honors Theses

Free-roaming cats have a devastating impact on wildlife populations with stray/feral cats being the most problematic. In some areas, community members provide these cats with food, water, and shelter often in conjunction with a trap, neuter, return (TNR) program. Hayden Island located north of Portland, Oregon is home to a managed colony of feral and stray cats. Some island residents provide feeding stations for the cats and actively participate in population management. To determine how feeding stations might affect cat spatial distribution, camera traps were placed at 19 different stations in urban and natural areas on Hayden island. Additional annual …

Connecting Environment And Phenotype: Deciphering Mechanisms Of Diapause Entry And Exit In The Annual Killifish Austrofundulus Limnaeus, Erin Monica Davis

Dissertations and Theses

Embryonic development is complex, dynamic, and dependent on environmental factors. Mechanisms of sensing and integrating environmental stimuli are diverse, and understanding these mechanisms in extant species can elucidate how complex phenotypes emerge from genomic information expressed in an environmental context. In Austrofundulus limnaeus, an annual killifish with alternative developmental trajectories, light and temperature are vital factors that determine if an embryo will enter a state of diapause. We hypothesize that embryos of A. limnaeus use the vitamin D₃ signaling pathway as a vehicle to incorporate these ecological signals into their developmental programing. Here we provide evidence of …

An Examination Of Limiting Factors Of Chrysemys Picta Bellii (Western Painted Turtles) In The Lower Willamette River Basin, Oregon, James P. Holley

Environmental Science and Management Professional Master's Project Reports

Oregon’s two native freshwater turtle species, Chrysemys picta bellii (Western painted turtle) and Actinemys marmorata (Northwestern pond turtle), have seen significantly reduced population sizes since the founding of Portland in 1845, with estimates of up to 90% for A. marmorata. This project examined turtle nesting activity at 25 sites across a range of turtle populations and habitats around the Lower Willamette River Basin. All discovered turtle nesting activity was found in areas of high solar exposure. We found 93% of over 400 nest attempts to have been depredated across the 25 sites, well above most other reported rates. At …

Interests And Priorities In Sockeye Salmon Management: How Are Policies Enacted And Interpreted On Three Alaskan Rivers?, Jake P. Palazzi

University Honors Theses

The large export abundance of Alaskan salmon is well documented, and many studies have been performed to assess the economic and environmental viability of the industry and its management. Less research has been done to characterize how state intentions regarding fisheries allocation are conceived of by management or perceived by vulnerable groups in the user pool. This study seeks to qualitatively characterize the disconnect between state and Native Alaskan perceptions of management effectiveness, public interest, and Native Alaskan involvement using interviews. Results showed that Native Alaskan and state manager respondents had very different perceptions of management effectiveness and equity. When …

Biogeography, Morphology, And Systematics Of The Mountain Cottontail, Sylvilagus Nuttallii (Bachman, 1837), Mammalia: Lagomorpha: Leporidae, Johnnie H. French

Dissertations and Theses

Widespread species often present taxonomic conundrums: are they truly a single panmictic species, or, is the widespread species in fact a polytypic species complex constituted by independently evolving, morphologically or otherwise cryptic species? One such broadly distributed taxon is Sylvilagus nuttallii, with distribution across the western United States, ranging from South Dakota to California, and from Canada to Arizona. The three subspecies constituting S. nuttallii are, however, geographically isolated and it has been hypothesized that they likely constitute independent, species level taxa. However, that study examined only two of the three holotypes, rather than broader geographic and non-geographic variation. …

Reviewing The Potential Link Between Grain-Free Diets And Dilated Cardiomyopathy In Canines, Larissa J. Webster

University Honors Theses

Grain-free diets for dogs are becoming increasingly popular, but concerns are emerging following the FDA's recent investigation that there might be a link between grain-free diets and Dilated Cardiomyopathy (DCM) in dogs with no known genetic predisposition. Contrary to the majority of the public thought, dogs do nutritionally require grains, and there is rarely a medical reason to switch to a grain-free diet. Not all cases of DCM are linked to diet, and many dogs who are fed grain-free diets do not develop the disease; the extent of this issue therefore is not entirely known. This review aims to explore …

A Methodological Review Of Resilience Approaches For Coral In The Face Of Climate Change, Gabriella L. Martinez

University Honors Theses

A literature review of research on Resilience Based Management Theory, Aquaculture, and Assisted Gene Flow and Evolution being explored as possible methods to help the coral bleaching crisis.

Proposal For Comparative Morphometrics Of Tübingen (Tu) And Tübingen Longfin (Tl) Zebrafish (Danio Rerio), Andrew Draper

University Honors Theses

The TL strain of zebrafish (Danio rerio) originated from the TU strain, and differs in fin pattern with a phenotype predominated by increased fin length. Two genes are known to affect the phenotype: leo and lof. The pattern-affecting leo gene is not believed to affect the growth rate, development, or proportionality of the body. The lof gene does however result in significant increase in fin length compared to the wild-type phenotype of TU. Using populations from both TL and TU genetic strains, development was observed from 48 hours post fertilization through sexual maturity at 90 days post fertilization …

Before And After The Storm: Interactions Between Tree-Fall Canopy Gaps, Plant Phenology, And Frugivorous Lemurs In Masoala National Park, Madagascar, Monica Sue Mogilewsky

Dissertations and Theses

Madagascar is one of Earth's top biodiversity hotspots, with 80% of life on the island considered endemic. Among the endemic species are lemurs, a diverse group of non-human primates. Unfortunately, Madagascar's diversity, including lemurs, is threatened by habitat degradation and loss. Despite intense anthropogenic pressure over the past 50 years, scientists have not detected any lemur extinctions during this period. Some researchers have proposed that lemurs' adaptations to natural disturbances have provided these taxa resiliency against anthropogenic disturbances. Certainly, Madagascar experiences an extreme disturbance regime: the island experiences an average of over three cyclones a year. These cyclones create numerous, …

Bone Mineral Density Of The Common Bottlenose Dolphin, Tursiops Truncatus: A Proposed Model For Monitoring Osteological And Ecosystem Health, James Wright Burrus Powell

Dissertations and Theses

Bone mineral density (BMD) in the pectoral flipper of the common bottlenose dolphin, Tursiops truncatus, was examined to address the need to define a comprehensive target site for clinical osteodensitometric assessment and to establish ranges of observed bone density values for this species. Radii were analyzed using dual energy X-ray absorptiometry (DXA), the accepted standard in human medical studies. Multiple loci within the radius were identified and assessed for their correlation to BMD of the entire bone. Radii BMD were also examined for differences based on sex, age, total body length, handedness, geographical affinity, and nutritional status at time …

Delphinids On Display: The Capture, Care, And Exhibition Of Cetaceans At Marineland Of The Pacific, 1954-1967, Taylor Michael Bailey

Dissertations and Theses

When Marineland of the Pacific opened in 1954 on the Palos Verdes Peninsula in greater Los Angeles, it was the second oceanarium in the world and the first on the West Coast. An initial investment of $3 million by Oceanarium Inc., owners of the popular Marine Studios park located near St. Augustine, Florida, ensured that Marineland was built with the same state of the art facilities needed to produce an authentic representation of the ocean floor on land. Building on Marine Studios' success exhibiting bottlenose dolphins (Tursiops truncatus), Marineland's central draw was its performing cetaceans. During the park's …

Whence And Whither: Acoustic Variability And Biogeography Of Tarsiers In North Sulawesi, Olivia Clare Kulander

Dissertations and Theses

The morning duet calls of eastern tarsiers (Tarsius spp.) in North Sulawesi were recorded and analyzed to examine the effects of geography and geologic history on their call structure. Tarsius species exhibit interspecifically variable duet calls shown to correlate with species differentiation and distribution. They are distributed across Sulawesi, a biogeographically complex island in the Indonesian archipelago, where tectonic activity and multiple glaciations during the Pleistocene generated and modified barriers to their dispersal and gene flow.

Recordings were made at ten locations from November of 2012 through June of 2014. Two locations were categorized as mainland, while eight island …

Intestinal Microbiota Diversity Of Pre-Smolt Steelhead (Oncorhynchus Mykiss) Across Six Oregon And Washington Hatcheries, Christina Carrell Yildirimer

Dissertations and Theses

The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, federal and state agencies annually release hundreds of thousands of hatchery-reared fish into the wild. However, accumulating data indicate that hatchery fish have lower fitness in natural environments, and that hatchery rearing negatively influences return rates of anadromous salmonids. Recently, mounting evidence revealed that the richness and diversity of intestinal microbial species influence host health. We examined the gut microbiota of pre-migratory hatchery-reared steelhead (Oncorhynchus mykiss) to assess …

Predicting Parturition In A Long-Gestating Species: Behavioral And Hormonal Indicators In The Asian Elephant (Elephas Maximus), Heather Kelly Velonis

Dissertations and Theses

Captive populations of Asian elephants (Elephas maximus) in North America are not self-sustaining, and increasing reproductive success within captive populations is a high priority. The ability to accurately predict parturition can have a direct impact on elephant welfare. Elephants in captivity often require significant preparation and management throughout the birthing process, and complications during labor and delivery can necessitate immediate intervention, including stillbirth, protracted labor, maternal aggression towards a newborn calf, and dystocia. Being able to predict when parturition will commence can ensure appropriate staff is available and adequate monitoring is performed. Routine endocrine sampling can be used …

Why Do Animals Do What They Do, When They Do It? Characterizing The Role Of The Hypothalamus-Pituitary-Adrenal Axis In Seasonal Life-History Transitions, Catherine Anne Dayger Forbes

Dissertations and Theses

Resource availability follows seasonal cycles in environmental conditions. To align physiology and behavior with prevailing environmental conditions, seasonal animals integrate cues from the environment with their internal state. One of the systems animals use to integrate those cues is the hypothalamus-pituitary-adrenal (HPA) axis and its primary effector, glucocorticoid hormones. The HPA axis has wide-ranging effects on physiology and behavior and, in the context of a glucocorticoid stress response, is known to mediate tradeoffs between immediate survival and future fitness. The HPA axis also plays an important role in facilitating predictable life-history events. Variation in HPA axis activity has been reported …

Quantifying The Impacts Of A Novel Predator: The Distinctive Case Of The Oregon Spotted Frog (Rana Pretiosa) And The Invasive American Bullfrog (Rana (Aquarana) Catesbeiana), Kyle Scott Tidwell

Dissertations and Theses

The decline of the Oregon Spotted Frog (Rana pretiosa), a Pacific Northwest endemic now federally listed as threatened, has been attributed to several aspects of ecosystem alteration, primarily habitat degradation and loss. The introduced American Bullfrog (Rana (Aquarana) catesbeiana) has been widely implicated in those declines, but the basis of that contention has been difficult to characterize. The bullfrog occurring at every site of recent Oregon Spotted Frog extirpation has focused concern about its impact.

Here, I present a suite of interconnected studies that examine the behavioral ecology of both species to better understand the potential …

Understanding The Importance Of Intermittently Fragmented Stream Habitat For Isolated Westslope Cutthroat Trout (Oncorhynchus Clarki Lewisi) In The Colville National Forest, Washington, Forrest Michael Carpenter

Dissertations and Theses

Climate change and anthropogenic effects have vastly reduced Westslope Cutthroat Trout (Oncorhynchus clarki lewisi, WCT) habitat throughout their range, including the Colville National Forest in northeastern Washington where this study was conducted. Many native salmonid populations have declined in abundance since the early 1900s due to a variety of climate- and human-driven forces. Westslope Cutthroat Trout are especially sensitive to habitat loss or degradation and to climate change. Together, climate change, habitat degradation, and non-native salmonid invasions are contributing to increasingly fragmented WCT populations. Ongoing and predicted future warming trends are expected to further fragment these populations and …

A Landscape Approach To Determining And Predicting Juvenile Coho Salmon (Oncorhynchus Kisutch) Movement Timing And Growth Patterns Prior To Ocean Entry, Amelia Lee Johnson

Dissertations and Theses

Coho salmon (Oncorhynchus kisutch) rely on unique habitats during the winter season, which may dictate how much individuals may grow and when migration from freshwater rearing habitat to the ocean occurs. Here I analyze movement timing and growth patterns for coho salmon through a field-based study and a literature review. For the field portion, I examined hatchery-stocked juvenile coho salmon across four stream basins in the Russian River watershed, California to determine the relative importance of climate, landscape, and fish size metrics in predicting movement and growth patterns over a winter rearing and spring smolt outmigration time period …