Ecology and Evolutionary Biology Commons^™

Fire And Road Disturbance Impacts On Forest Plant Species And Seed Rain In Table Mountain Fire Arai, Kittitas County, Washington, Jonathan A. Betz

All Master's Theses

Forest communities are in a constant state of change. Disturbance events can alter the physical landscape and create conditions favorable to some species while negatively impacting others. Fire has been a natural, reoccurring source of disturbance in Pacific Northwest forests. Over the past centuries the fire paradigm has changed in favor of fire suppression. Forest roads permit access provide greater access but further fracture forest community’s continuity. The 2012 Table Mountain Fire and road influence have altered the plant community’s seed rain and vegetation. This study measured dispersed seeds and understory vegetation cover as functions of roads and fire intensity. …

Ecological Consequences Of Sea Star Wasting Disease: Non-Consumptive Effects And Trait-Mediated Indirect Interactions From Pisaster Ochraceus, Timothy Ian Mcclure

Cal Poly Humboldt theses and projects

Consumptive effects (CEs) of predators are an important factor in structuring biological communities, but further work is needed to understand how the interaction between spatial and temporal differences in predator density affects non-consumptive effects (NCEs) on prey. NCEs can cause indirect effects on food resources, known as trait-mediated indirect interactions (TMIIs), and thus can also affect community structure. However, few studies have considered the relationships between spatial and temporal predator density variation and the strength of NCEs and TMIIs in the natural environment. The ochre star Pisaster ochraceus is common predator of the herbivorous black turban snail Tegula funebralis, imposing …

Estimating Space Sharing Between Seabird, Pinniped, And Human Use In The Northern California Coast, Claire Marie Nasr

Cal Poly Humboldt theses and projects

Rocky coastlines incur high impacts from human use, but these places are also essential habitat for marine wildlife including seabirds and pinnipeds (seals and sea lions). Marine wildlife use coastal rocks to breed, rest, and engage in social interaction and exhibit different habitat use during the breeding and non-breeding season. Peak timing of human use occurs in spring summer, coinciding with breeding seasons for colonial seabirds and gregarious pinnipeds. The high potential of spatial and temporal overlap between human and seabird use of rocky coastlines could lead to high risk of disturbance events. I investigated the relative risk of disturbance …

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 …

Effectiveness Of Snap And A24-Automated Traps And Broadcast Anticoagulant Bait In Suppressing Commensal Rodents In Hawaii, Aaron B. Shiels, Tyler Bogardus, Jobriath Rohrer, Kapua Kawelo

Human–Wildlife Interactions

Commensal rodents (invasive rats, Rattus spp.; house mice, Mus musculus) are well established globally. They threaten human health by disease transfer and impact economies by causing agricultural damage. On island landscapes, they are frequent predators of native species and affect biodiversity. To provide managers with better information regarding methods to suppress commensal rodent populations in remote island forests, in 2016 we evaluated the effectiveness of continuous rat trapping using snap-traps, Goodnature^®A24 self-resetting rat traps, and a 1-time (2-application) hand-broadcast of anticoagulant rodenticide bait pellets (Diphacinone-50) applied at 13.8 kg/ha per application in a 5-ha forest on Oahu, …

Harnessing Population Genetics For Pest Management: Theory And Application For Urban Rats, Matthew Combs, Kaylee Byers, Chelsea Himsworth, Jason Munshi-South

Human–Wildlife Interactions

Effective management of rodent pests requires an ecological understanding of how they move through their environment and how those movements influence the invasion, persistence, or reinvasion of problematic colonies. Traditional methodologies used to describe rodent movement patterns, such as mark-recapture, are hindered by their time-consuming nature and limited geographic scope. As such, our understanding of how rodents interact with urban environments remains limited. Population genetic principles and tools have the capacity to greatly increase our understanding of rodent population dynamics, ecological relationships, and movements across space, but this field is often unapproachable to non-scientist pest management professionals (PMPs). In this …

Efficacy Of An Online Native Snake Identification Search Engine For Public Use, Scott E. Henke, Samantha S. Kahl, David B. Wester, Gad Perry, David Britton

Human–Wildlife Interactions

Visual methods of species identification are used both in research and recreational contexts because they are inexpensive, non-invasive, and believed to be effective among uniquely identifiable individuals. We examined the ability of the general public to identify live snakes (Serpentes) that are native to the United States using an online snake identification search engine (SISE) produced by the North America Brown Tree Snake Control Team (NABTSCT) website, http://www.nabtsct.net. The SISE consisted of participants answering 7 descriptive questions concerning a snake and then reviewing photographs of snakes that matched that description. Using 3 species of snakes native to Texas, USA, 21% …

Upper Thermal Limits Vary Among And Within Native Bee Species In Relation To Season, Voltinism, And Nest Type, Kálmán K. Csigi Xiv

Theses and Dissertations

Native bees are only recently gaining attention for the extent to which they aid in pollination and ecosystem services. These services are threatened by predictions of warming temperatures if bees are not able to respond. Voltinism - the number of generations produced annually- can strongly influence thermal conditions experienced by both developing and adult bees based on emergence strategies for each voltinism type. Differences in experienced thermal conditions brought on by climate change could therefore affect upper thermal limits (UTL) in bees. This study observes UTLs across a foraging season within and among native bee species vi to elucidate the …

Tiger Sharks Eat Songbirds: Scavenging A Windfall Of Nutrients From The Sky, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, E. A. Seubert, A. E. Jefferson, A. M. Kroetz, Sean P. Powers

University Faculty and Staff Publications

No abstract provided.

Evidence For A New Search Behavior: Porcupines “Scout” For Winter Habitat During Summer In A Coastal Dune System, Pairsa N. Belamaric

Cal Poly Humboldt theses and projects

Species are often challenged by periodic changes in food availability and habitat quality. These environmental conditions may provide strong selective pressure for animals to strategically "scout" for important resources during periods of abundance, when exploratory movements are less costly. North American porcupines experience a drastic shift in forage quality from summer - a time of abundant, high quality forage - to winter, a nutritional bottleneck. I evaluated potential scouting behaviors of porcupines in Tolowa Dunes State Park, California using movement and habitat-use data. I compared summer and winter space use of porcupines using GPS data and monitored seasonal use of …

Tree Squirrels And Fishers In Northern California: The Effects Of Masting Hardwoods On Stand Use, Andria M. Townsend

Cal Poly Humboldt theses and projects

In western North America, tree squirrels such as western gray (Sciurus griseus) and Douglas squirrels (Tamiasciurus douglasii) are potentially important prey for fishers (Pekania pennanti). Western gray squirrels in particular may be highly ranked due to their large body size. Masting trees including black oak (Quercus kelloggii) and tanoak (Notholithocarpus densiflorus) produce an important food source for tree squirrels; therefore, forest stands containing these trees may be useful to foraging fishers. I hypothesized that; 1) the abundance of western gray and Douglas squirrels in a stand is influenced by the …

Testing For Cryptic Diversity And Inference Of Population Structure In The Cosmopolitan Hoplonemertean Emplectonema Gracile (Nemertea), Paul L. Delaney Iv

Theses and Dissertations

Emplectonema gracile (Johnston 1837) is a hoplonemertean of marine intertidal hard-bottom communities and is distributed throughout the Northern Hemisphere. Although possessing a planktonic larval stage in its life history, the range of such cosmopolitan marine invertebrate species is often explained by cryptic speciation and anthropogenic transport. The purpose of this study is to test for possible cryptic species using mtDNA markers (COI and 16S rDNA) and to investigate population structure in E. gracile over a portion of its geographic range using mtDNA markers and ddRADseq nuclear SNP data. The results of both phylogenetic- and tree-based species delimitation revealed that E. …

Examining Aspen Expansion From Before And After Prescribed Burning In A Native Fescue Grassland Through Geospatial Techniques, Christopher Anderson

Dissertations, Master's Theses and Master's Reports

Native fescue (Fescue spp.) grasslands of the Intermountain West have become increasingly scarce due to the advent of modern agriculture, the loss of Indigenous people’s land management practices, modern wildfire management and the extirpation of bison (Bison bison bison). Native grassland is a biodiversity hot-spot, is significant for carbon sequestration, and essential to many species of flora and fauna that occur in the ecosystem. Our study site, on the Rocky Mountain Front in Waterton Lakes National Park, Alberta Canada, consists of 30 discrete aspen stands (Populous tremuloides) which are encroaching on this declining shortgrass fescue …

Shaping The Tools Of Battle : Sexual Selection, Contest Dynamics, And Weapon Divergence In The Asian Rhinoceros Beetle Trypoxylus Dichotomus, Jillian F. Del Sol

Graduate Student Theses, Dissertations, & Professional Papers

Exaggerated weapons of sexual selection often diverge more rapidly and dramatically than other body parts, suggesting that relevant agents of selection may be discernible in contemporary populations. I examined the ecology, reproductive behavior, and strength of sexual selection on horn length in five recently diverged beetle populations that differ in relative horn size. I show that mating system ecology differs between these locations and corresponds with the local strength of contemporary selection on horn length. Comparisons of ecological conditions and selection strength across populations offer a critical first step towards meaningfully linking mating system dynamics, selection patterns, and diversity in …

Life History Of The Coastal Tailed Frog (Ascaphus Truei) Across An Elevational Gradient, Adrian Daniel Macedo

Cal Poly Humboldt theses and projects

The life history of a species is described in terms of its growth, longevity, and reproduction. Unsurprisingly, life history traits are known to vary in many taxa across environmental gradients. In the case of amphibians, species at high elevations and latitudes tend to have shorter breeding seasons, shorter activity periods, longer larval periods, reach sexual maturity at older ages, and produce fewer and larger clutches per year.

The Coastal Tailed Frog (Ascaphus truei) is an ideal species for the study of geographic variation in life history because it ranges across most of the Pacific Northwest from northern California …

Evaluation Of Range-Wide Occupancy And Survey Methods For The Giant Kangaroo Rat (Dipodomys Ingens), Alyssa E. Semerdjian

Cal Poly Humboldt theses and projects

Though habitat suitability and occupancy are often correlated, they cannot always be inferred from each other. Therefore, a solid understanding of both is essential to effectively manage species. Recent studies have assessed range-wide habitat suitability for the giant kangaroo rat (Dipodomys ingens; GKR), but data regarding occupancy is lacking in parts of its distribution. Satellite and aerial imagery were used to identify GKR burrows across their known range, producing a range-wide occupancy map and non-invasive survey methods including track plates, manned flight, unmanned aerial vehicle, and sign surveys were conducted to determine effective methods for monitoring GKR occupancy. …

Competition Or Facilitation: Examination Of Interactions Between Endangered Sida Hermaphrodita And Invasive Phragmites Australis, Samantha N. Mulholland

Theses and Dissertations (Comprehensive)

Virginia Mallow (Sida hermaphrodita) is a perennial herb of the Malvaceae family that is native to riparian habitats in northeastern North America. Throughout most of its geographical distribution however, it is considered threatened and only two populations are known from Canada. The biology and ecology of S. hermaphrodita are still poorly understood and although few studies have been performed to determine the factors that contribute to the species rarity, it is considered threatened potentially due to the loss of habitat caused by exotic European Common reed (Phragmites australis subsp. australis) invasion. Allelopathic and phytotoxic conditioning of …

Intraguild Predation: Interactions Between Predators, Pathogens, And Their Shared Resources In Crop Pest Communities, Andrew Jason Flick

LSU Doctoral Dissertations

Crop pest management requires an understanding of the complex interactions among pest species that potentially damage crop yield and species that may be crucial for controlling pest species outbreaks. For example, predators, parasitoids, and pathogens are constantly interacting via their shared prey or hosts. Predators may prefer infected prey, which can be easier to catch; however, infected prey may be less nutritious or even lethal for predators. These interactions then dictate the short-term dynamics of host and pathogen as well as between prey and predator. "How these dynamics change as the species in the system change either empirically or theoretically?" …

A Change In Grain? Diet Induced Plasticity In The Generalist Grasshopper Melanoplus Differentialis, Austin M. Culotta

LSU New Orleans Theses and Dissertations

Phenotypic plasticity is favored in heterogeneous environments in which alternative phenotypes can exploit alternative resources. However, it’s not clear whether phenotypic plasticity is useful in environments that become more homogenous over an organism’s life cycle. I studied a population of grasshopper Melanoplus differentialis that experiences high resource diversity as nymphs but low resource diversity as adults to determine if individuals can undergo diet-induced morphological plasticity in head shape to increase biting ability and ingestion of hard diets. Insects on a soft diet were larger and had greater bite force than those on a hard diet. Head structures related to chewing …

Engineering Eden: The World's Attempt To Outsmart Water Scarcity, Kaitlin A. Sullivan

Capstones

Countries around the world are running out of fresh water, 43 already live with water scarcity, requiring more water than they have. In 2015 the global water crisis took first place in The World Economic Forum’s assessment of the risks that will have the most significant impact on economies, environments and people. Water beat out 27 other long-term risks including infectious diseases and weapons of mass destruction. What happened to Crowley County on the plains of Southeastern Colorado is a cautionary tale of borrowed water. It's been called the Detroit of Colorado, decimated by the reliance of a single industry. …

The Thermal Ecology Of Sceloporus Occidentalis, Luis Patricio Burgos

Master's Theses

With temperatures rising globally, assessing the possible impacts of the changing climate becomes more and more urgent. Ectotherms are excellent indicators of potential climatic ramifications on biodiversity because of their heavy reliance on the environment for their thermoregulation. Studies have historically looked at thermal tolerance values to establish predictive models for population and species extinctions.

In chapter 1, we looked at recent studies that suggest that thermal tolerance may be a plastic trait and test the effects empirically. Most studies are based on captive lizards acclimated to laboratory conditions that do not necessarily reflect natural environments, and if thermal tolerance …

The Biological Significance And Utility Of Feeding By Dermestes Maculatus, Braymond Adams

School of Natural Resources: Dissertations, Theses, and Student Research

With their efficient feeding habits and tolerance to very low moisture and humidity, beetles in the Family Dermestidae are especially adapted to variable environments and habitats. Dermestid cultures have been in use since 1922 in cleaning tissue and flesh from bones, and proven benefit in multiple fields, including zoology, ornithology, and forensics. Dermestid feeding behaviors when coupled with known life stage and insect succession information aids in providing significant entomological evidence. However, the feeding activities of insects, like those of vertebrate scavengers and predators, change remains and may leave artifacts that can be sometimes be difficult to assign to a …

Safety, Stephen M. Vantassel, Brenda K. Osthus

Wildlife Damage Management Technical Series

Wildlife damage management (WDM) is an exciting field with many opportunities to provide solutions to the complex issues involved in human-wildlife interactions. In addition, WDM wildlife control operators (WCO) face a variety of threats to their physical well-being. Injuries can result from misused (Figure 1), faulty, or poorly maintained equipment, inexperience, mishandled wildlife, harsh weather, and dangerous situations, such as electrical lines. The goals of this publication are to: * Develop an awareness of safety issues and adopt a mindset of “Safety First”, * Review the major safety threats that WCOs face, * Provide basic information for WCOs to protect …

Courtship Behavior, Communication, And Copulation In Tigrosa Annexa, Samuel White

Scholars Week

The evolution of multimodal communication, where signalers use multiple signal components in multiple sensory modalities, has become the subject of investigation by many researchers. Signaling puts males at risk of predation, so why do males of some species evolve extra signals that may increase this risk? In some wolf spider species, males incorporate many visual and vibrational signals into a display that they use to attract a female for mating. Female spiders are often aggressive toward courting males and so the male display also functions to decrease the odds of cannibalism. Female wandering spiders deposit silk containing pheromones that communicate …

No Evidence For Kin Protection In The Expression Of Sickness Behaviors In House Mice, Patricia C. Lopes, Per Block, Alice Pontiggia, Anna K. Lindholm, Barbara König

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

When infected, animals change their behaviors in several ways, including by decreasing their activity, their food and water intake, and their interest in social interactions. These behavioral alterations are collectively called sickness behaviors and, for several decades, the main hypotheses put forward to explain this phenomenon were that engaging in sickness behaviors facilitated the fever response and improved the likelihood of host survival. However, a new hypothesis was recently proposed suggesting that engaging in sickness behaviors may serve to protect kin. We tested this kin protection hypothesis by combining a field and a laboratory experiment in house mice. In both …

Embryonic Origin And Genetic Basis Of Cave Associated Phenotypes In The Isopod Crustacean Asellus Aquaticus., Hafasa Mojaddidi, Franco Fernandez, Priscilla A. Erickson, Meredith E. Protas

Natural Sciences and Mathematics | Faculty Scholarship

Characteristics common to animals living in subterranean environments include the reduction or absence of eyes, lessened pigmentation and enhanced sensory systems. How these characteristics have evolved is poorly understood for the majority of cave dwelling species. In order to understand the evolution of these changes, this study uses an invertebrate model system, the freshwater isopod crustacean, Asellus aquaticus, to examine whether adult differences between cave and surface dwelling individuals first appear during embryonic development. We hypothesized that antennal elaboration, as well as eye reduction and pigment loss, would be apparent during embryonic development. We found that differences in pigmentation, eye …

The Paradoxical Giant Hummingbird: Comparison Of Andean And Coastal Subspecies With Respect To Blood, Migration, And Genes, Jessie L. Williamson

Shared Knowledge Conference

The Giant Hummingbird (Patagona gigas) is twice as large as the next largest hummingbird species and has long been considered paradoxical with respect to flight biomechanics. It is also an extreme outlier in other respects. For example, it is the only hummingbird species that breeds above 4,000 m elevation and also along the beaches of the Pacific Ocean. The high Andean populations of Giant Hummingbird (P. g. peruviana) that we have studied previously have a beta-hemoglobin genotype (serine at beta-hemoglobin A positions 13 and 83) that is characterized by high O2-affinity and is only shared with four unrelated hummingbird taxa …

Examining Patterns In Nest Predation Using Artificial Nests, Victoria L. Simonsen

School of Natural Resources: Dissertations, Theses, and Student Research

The use of artificial nests to study the predation of avian nests has faced disregard by ecologists due to inconsistencies found between the survival rates of real and artificial nests across studies and reviews. The negative perception of artificial nests providing an inconsistent assessment of survival has thus fostered the perception that artificial nests are a secondary option to be used to overcome logistical hurdles associated with achieving sufficient sample sizes in systems where study species are rare or elusive, or as merely a preliminary method to study predation across gradients. We argue that the greatest mistake ecologists have made …

Contemporary Sunday Hunting Laws: Unnecessary Economic Roadblocks, Ripe For Repeal, Seamus Ovitt

William & Mary Environmental Law and Policy Review

In America, Sunday closing laws, laws restricting what activities individuals could engage in, date back to the early colonial period; those early laws, like much of North American jurisprudence, trace their roots to the laws that existed in England at the time. Historically, however, laws restricting the behavior of individuals, specifically on Sundays, date back thousands of years; initially, their language was tied directly to that of the Old Testament. As God declared:

[s]ix days shalt thou labour, and do all thy work: But the seventh day [is] the Sabbath of the Lord thy God: [in it] thou shalt not …

Theory On Thermodynamic Constraints To Biogeochemical And Metabolic Diversity, Jordan Okie, Everett Shock

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.