Variation at mitochondrial D-loop sequences and microsatellite loci were studied in three sub-populations of recently introduced red foxes (Vulpes vulpes) in California. Red foxes were introduced separately in northern and southern California near the . . .

Bioassessment utilizes biological assemblages to assess ecological condition in disturbed areas. The most popular quantitative evaluation of biological health in streams involves an Index of Biotic Integrity (IBI) for benthic macroinvertebrates (BMIs) . . .

Coastal ecosystems are under intense pressure from anthropogenic and environmental factors in California. Human development, pollution and climate change continue to degrade coastal habitats. Marine predators such as marine mammals that depend on near . . .

The flowers of the California pitcher plant, Darlingtonia californica, are unusual and have been the subject of much speculation. Despite the efforts of several workers, the pollination ecology of this plant, including the identities of pollinators, r . . .

I describe the spatial and temporal distribution, abundance and habitat use of Steller sea lions (Eumetopias jubatus) in northern California between 2006 and 2011 obtained through shore and at-sea surveys and by tracking branded individuals. Understan . . .

Coastal shrublands of Humboldt and Del Norte Counties, California were classified and described based on data from 140 plots sampled at 46 sites. Twinspan was used to separate plots into groups. Indicator species analysis was used to determine which s . . .

To obtain the most complete understanding of a species’ life history requirements, one must know what habitat characteristics and resources are critical to each life history stage. Rana boylii are known to associate with various stream habitats throug . . .

A population of Eumetopias jubatus and Zalophus californianus was studied during the summers of 1983 and 1984 on the coast of Humboldt County. The population of E. jubatus and Z. californianus peaked during June and August. Z. californianus numbers pe . . .

The vascular transport system of most flowering plants is composed of vessels that are responsible for bulk axial water transport. Transport through vessels may become blocked by gas emboli following freeze-thaw events because gasses come out of solut . . .

Humboldt Bay contains two populations of eelgrass; Zostera marina L., a sparse population in North Bay and a significantly denser population in South Bay. No study has attempted to determine the cause of this density difference despite the importance . . .

Human population growth and rapid urbanization have created new, attractive environments for opportunistic animals including some species of wild canids. San Joaquin kit foxes (Vulpes macrotis mutica) are a federally listed endangered and California . . .

Habitat modeling techniques are widely used to determine where species occur on the landscape and what habitat or environmental factors influence their presence. These techniques are particularly useful for rattlesnakes, which have life history traits . . .

Mytilus californianus beds along the wave-exposed coast of the eastern North Pacific Ocean serve as an important habitat, harboring a high diversity of species due to their colonizable hard surfaces as well as through the creation of microhabitats wit . . .

Many conservation strategies for bats focus on supporting or enhancing their roosting and foraging needs. With increasing urbanization and loss of natural habitat, many species have adapted to roost in anthropogenic structures, resulting in increased . . .

Nonpathogenic bacterial endosymbionts have been shown to contribute to their arthropod hosts’ fitness by supplying them with essential vitamins and amino acids. Little is known about the nutritional basis for the symbiotic relationship of endosymbiont . . .

Plecoptera (stoneflies) were collected during the spring emergence in the Willow Creek basin, Humboldt County, California. Both adults and nymphs were collected using qualitative methods. Water chemistry, substrate size, and riparian vegetation were u . . .

Boiling Springs Lake (BSL) is a 52˚C, pH 2, iron and sulfur-rich thermal feature in Lassen National Volcanic Park (California, USA). Previous community composition studies of small subunit rRNA and RuBisCo genes revealed an abundance of phylotypes clo . . .

The following research addresses the question: does color vision occur in animals that can only see rudimentary images? Since the morphological and neurological requirements of color vision are minimal relative to those necessary for image formation, . . .

Lithobates catesbeianus (American bullfrogs) are not native to states west of the Rocky Mountains. Since their introduction to California, they have been implicated in the decline of amphibian species. On California’s north coast, bullfrogs may be cau . . .

A great effort has been made in the last few decades to restore and preserve coastal dunes in northwest California. The restoration effort has largely focused on removal of invasive plants, with little study on how invasive plant removal affects nativ . . .

This study examined how pollinator visitation and local neighborhood density may affect pollen limitation (PL) of reproductive success for Vancouveria chrysantha Greene (Berberidaceae), a rare plant, strictly endemic to serpentine substrates in northw . . .

A number of isolated high temperature, low pH geothermal sites exist in Lassen Volcanic National Park (LVNP) and Hawai’i Volcanoes National Park (HVNP) that allow for the growth of thermoacidophilic microbial communities. Horizontal gene transfer (HGT . . .

The tallest tree species, coast redwood (Sequoia sempervirens), provides an ideal model for investigating both the adaptations allowing maximum height growth in plants and the factors that limit it. Within the crowns of tall redwoods there exists broa . . .

A total of 17 transgenic strains of Caenorhabditis elegans were evaluated for use as bioindicators for the presence of toxins in an environmental sample. Every strain used had Green Fluorescent Protein (GFP) production driven by the promoter region of . . .

Different loci within a multigene family often experience unique evolutionary pressures; this phenomenon is often observed in proteins involved in reproduction. Chemical communication using secreted proteinaceous pheromones is critical for reproductiv . . .

The relationship between eelgrass bed characteristics and animal use is important in better understanding what the optimal habitat features are for specific taxa. The focus of this study was to look at structural and geographical aspects of eelgrass h . . .

In this study, I examined the effects of FMRFamide on the isolated crop-gizzard of the earthworm, Lumbricus terrestris. The peptide induced contractions of both the longitudinal and circular muscles of the crop-gizzard at concentrations examined (10-9 . . .

The South Fork Trinity River is an undammed river in Northern California that drains a watershed with a long history of varied anthropogenic uses including mining, logging, cattle grazing, and associated road construction. These activities modify ripa . . .

This study examined changes in Sequoia sempervirens foliage along gradients of height and light availability. In tall trees (108-113 m), shoot morphology and physiology were analyzed at the base of the live crown, the mid-crown, and treetop. Both ligh . . .

Many turtle species require aquatic and terrestrial habitats during different times in their life history for foraging, mating, nesting, estivation and overwintering. The status of many turtle populations depends directly on the condition of both envi . . .

Determining the factors that shape arthropod communities has a long history in ecology. I examined the direct and indirect effects of nitrogen availability on plant productivity and plant community composition to assess their effects on arthropod comm . . .

Oct4 is a POU class V transcription factor that functions to maintain the pluripotent state of embryonic stem cells by activating or repressing the transcription of hundreds of target genes (Boyer et al. 2005). Aberrant expression of Oct4 has been rep . . .

Habitat fragmentation can have negative effects throughout an ecosystem, but its impact is dependent on the spatial scale at which community members respond to the environment. Because solitary bees are central-place foragers, their access to floral r . . .

Eight species of the ectomycorrhizal (ECM) genus Sarcodon (Bankeraceae, Thelephorales, Basidiomycota) are described as new to science. Sarcodon quercophilus, and Sarcodon umbilicatus are described from Quercus (Fagaceae) cloud forests within the Maya . . .

Boiling Springs Lake is a pristine, oligotrophic, acidic hot spring in Lassen Volcanic National Park. In 2008, 25 isolates from BSL were tested for resistance to 14 different antimicrobial compounds or a sub-set of the 14 antimicrobial agents. All iso . . .

Nearly all animals are able to detect forms of chemical stimuli. In amphibians, chemoreceptive capabilities are used in a wide variety of contexts, including the detection of predators, conspecifics, and food. The focus of this project was the use of . . .

Desert water courses are topographically distinct features with periodic flooding, which are floristically rich and structurally complex. This study was undertaken to determine if plant species and vegetation types change along desert water courses as . . .

In 1992 the rapidly developing demand for taxol led to consideration of a possible Pacific yew harvest in northwestern California. Deer browsing has prevented regeneration of Canada yew in some areas. Knowing that deer populations have been high in th . . .

Predictions of low genetic variation and low levels of inbreeding depression in small plant populations were tested on Astragalus agnicidus, a species with only one known population. Loss of alleles through drift and increased inbreeding (followed by . . .

Spotted Fever Group (SFG) Rickettsiae are important zoonoses affecting both people and dogs. Rocky Mountain spotted fever (RMSF) caused by Rickettsia rickettsii, is the most well-known zoonotic SFG; historically in California cases were identified fro . . .

Diaulula sandiegensis (Cooper, 1862), a northern Pacific nudibranch, has considerable phenotypic variation in dorsal spotting pattern throughout its range. Experiments were conducted to test the possibility that D. sandiegensis is a complex of unrecog . . .

This work is a taxonomic study of nine species in the ectomycorrhizal fungal family Boletaceae (Basidiomycota) from Neotropical rainforests of Guyana, in northeastern South America. Morphospecies collections from the following genera were studied: Tyl . . .

Understanding the effects of biotic and abiotic pressures on commercially important marine species is crucial to their successful management. The red abalone (Haliotis rufescensis) is a commercially important mollusc, whose shell surface is frequently . . .

Bees (Hymenoptera) represent one of the primary pollinators in most natural and managed ecosystems world-wide. Current concerns for a global decline in bee populations emphasize the need to better understand the factors that shape bee communities. Alt . . .

The Oregon spotted frog (Rana pretiosa), endemic to the Pacific Northwest, was once considered widespread in complex, warm water wetlands. Over 70% of historic populations are thought to be extirpated with range-wide habitat loss exceeding 90%. Using . . .

Due to the many misconceptions about science and the general lack of scientific literacy in our society, there is a need to better distribute accurate, comprehensible scientific ideas in an engaging way. Science education films can be powerful tools i . . .

Ultramafic parent materials in northern California and southwestern Oregon have given rise to one of the largest serpentine regions in the world. This area is dominated by sparse, fire-prone coniferous forests and shrublands which are apparently highl . . .

Marine fouling communities contain a plethora of sessile colonial invertebrates. These invertebrates come in many different shapes which occupy space and compete for resources in different ways. It has been theorized that these organisms be placed int . . .

Forest stands occurring on coastal dunes along the western margin of Humboldt Bay, California are isolated fragments of a regional forest type that stretches discontinuously along the Pacific Coast from northern California to Alaska. I used aerial pho . . .

Although many studies have investigated the effect of invasive plants on native plant species, few studies have considered their effect on pollination success. Since invasive plants potentially compete with native plants for pollinator services, the f . . .

Point count and species-specific surveys are widely used to infer avian abundance and species richness. However, advancements in bioacoustic technology enable automated survey alternatives that can expand the landscape coverage with equivalent personn . . .

As populations of a species decline, an understanding of habitat use and regional variation in population health can aid in focusing conservation efforts. Western Pond Turtle (Actinemys marmorata) populations have declined throughout much of their ran . . .

Over the past several years, ecologists have begun to recognize that the role played by positive plant-plant interactions, specifically facilitation, in communities is under appreciated. Despite this recognition, little is known about how these positi . . .

The North East Pacific coastline is a diversity hotspot for many marine organisms, including seaweeds, which live in complex habitats influenced by tectonics, glaciation, and ocean circulation. This is the first study to thoroughly survey population g . . .

Riffle sections of eight streams in northern California were sampled for aquatic insects using a kick net. Eleven chemical and physical stream parameters were measured at each riffle sampled. Biological data was analyzed using Simpsons diversity index . . .

In forests native pathogens accelerate tree decline, increase stand structural heterogeneity, and alter tree community composition. In northern California, white fir (Abies concolor var. lowiana) and Douglas-fir (Pseudotsuga menziesii var. menziesii) . . .

The southern distribution of the northern red-legged frog (Rana aurora) extends only into the three most northern coastal counties of California and seems to be restricted to the coastal belt. Because of recent declines in the population and destructi . . .

Bat migration ecology is an important, yet understudied facet of natural history and conservation. We know little about the movement patterns of migrating bats and the physiological demands that bats experience in preparation for and during migration. . . .

Napa County is located within a global biodiversity hotspot, and is one of ten localized areas in California that contain the highest numbers of native and endemic plant species. Conservation of rare taxa is an important issue and the research present . . .

Genetic structure and diversity of populations can impact the productivity and resilience of ecosystems. In Humboldt Bay, California (USA) eelgrass (Zostera marina) is the dominant marine plant at low intertidal and shallow subtidal elevations where i . . .

The Great Gray Owl (Strix nebulosa) is listed as a State of California endangered species due to their low population of approximately 100 individuals. Annual surveys and long-term monitoring efforts are frequently conducted to determine the status of . . .

Increased suspended sediment inputs to streams as a result of human activities and disturbance have been identified as a principle source of stream impairment. Allochthonous energy inputs to riverine food webs, in the form of terrestrial leaf litter, . . .

Populations of flying squirrels occupying oak and oak-pine forests of the Mesoamerican highlands represent the least studied and most poorly known members of the genus Glaucomys. Traditionally, these Mesoamerican populations have been considered to be . . .

Humboldt Bay, in far northern California receives a large amount of sediment, predominantly silts and clays from the surrounding watersheds at an estimated 62,532 metric tons/yr. (Barrett 2004). Fine grained sediments such as silts and clays have a hi . . .

Studying the impacts on a community following the introduction of an exotic species is of increasing importance in the field of marine science. Recent investigations of marine biological invasion have primarily focused on studying the negative interac . . .

The disease chytridiomycosis has caused population declines in hundreds of amphibian species worldwide, and is caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd). One promising method to combat the disease is to augment the amphibian’ . . .

For over a century, increases in the abundance of woody plant species in savannas have been occurring worldwide, and this woody plant encroachment directly threatens the existence of savanna ecosystems. Savannas are known for their striking compositio . . .

The genus Ribes displays extensive floral diversity. The pollinator shift model suggests that such diversity is an outcome of species shifting to specialize on new pollinators. To test this model, I surveyed the flower visitors of 14 Ribes species at . . .

Numerous studies have analyzed the effect of habitat fragmentation on plant pollinators and herbivores. These studies describe the decrease in pollinator services and seed set in small and isolated patches due to pollinator preference for large, conti . . .

The dominant plant in Humboldt Bay salt marshes is Spartina densiflora, a species of cordgrass apparently introduced from South America. At several salt marshes and restoration sites around Humboldt Bay, distribution of this plant has increased signif . . .

Spotted fever group (SFG) rickettsiae have been shown to cause many human and animal diseases. SRG rickettsial phylotypes G021 and G022 were recently detected in Ixodes pacificus ticks from Napa and California using quantitative real time polymerase c . . .

Disturbances such as wildfire play a major role in the diversity, structure, and composition of plant communities, however, little is known about the differential impacts of fire across landscapes that vary in characteristics such as soil nutrients an . . .

Chalcones are aromatic ketones that form the central core for a variety of important biological compounds. Previous research in Dr. Calderón-Urrea’s laboratory showed the efficacy of eight chalcones (1, 16, 17, 18, 19, 22, 25, and 30) to kill Caenorha . . .

Chalcones are aromatic ketones that form the central core for a variety of important biological compounds. Previous research in Dr. Calderón-Urrea’s laboratory showed the efficacy of eight chalcones (1, 16, 17, 18, 19, 22, 25, and 30) to kill Caenorha . . .

Five species of western gooseberries (Ribes: Grossulariaceae) hybridize to varying degrees in northwestern California and southwestern Oregon. Pollinator surveys and hand-pollination experiments were conducted to identify reproductive barriers between . . .

Harbor seals have been listed as a species likely to benefit from new Marine Protected Areas (MPAs) in California as part of the Marine Life Protection Act. Whereas seals may experience direct and indirect effects from these MPAs as a whole, the impac . . .

The discovery of antitoxins to both diphtheria and tetanus toxins dramatically introduced two immunological phenomena to twentieth-century science. First, biologically active molecules, such as toxins and enzymes, may have the potential to be neutr . . .

Xylem is a complex vascular tissue that performs several functions related to the growth and survival of woody plants. These functions include the transport of water, biomechanical support, and the storage of water and nutrients. Trees are large organ . . .

Sculpins of the genus Cottus are commonly found in brackish water and streams of the Pacific drainage of North America (Morris, 1961). Though common, they are infrequently encountered being small, bottom dwelling fish, rarely exceeding 1 50 mm S. . . .

Global-change-type drought has resulted in large numbers of woody plants suffering mortality in California during the most recent droughts from 2012-2018. These droughts are ecological droughts that impact ecosystems and trigger responses. The factors . . .

Sandy beaches support dynamic and diverse, but physically narrow intertidal ecosystems that are vulnerable to the effects of anthropogenic disturbance, such as coastal dredging and beach nourishment. Our study site in Morro Bay, California has been . . .

Fewer than 40% of students that pursue college degrees in Science, Technology, Engineering, and Mathematics (STEM) do not graduate with a STEM degree. The rate of college degree attainment in STEM is about 20% lower for women, people with disabiliti . . .

Invasive annual grasses of mediterranean origin dominate large areas in the arid and semi-arid regions of the San Joaquin Valley in California and create numerous management challenges. Much of the invaded habitat would be native saltbush shrub commun . . .

Bladderworts, aquatic carnivorous plants, use specialized traps (with a mouth opening of about 0.2 mm in diameter) to complete their feeding strike in less than a millisecond after the trap begins to open. Suction feeding is well understood in animals . . .

Coccidioidomycosis, also known as Valley Fever, is a re-emerging infectious disease of the American continent. Coccidioidomycosis is a respiratory disease caused by the inhalation of arthroconidia produced by the dimorphic ascomycete fungi Coccidioide . . .

In order to further investigate the presence of these antibiotic biosynthetic pathways, this study focused on ten genes and the identification of genes that code for enzymes in these antifungal and antibacterial pathways; Flagellin (hag), Mucosubtilin . . .

My results suggest that Desert Kit Foxes in the Mojave Desert in California prefer to consume rodents and invertebrates, but will prey upon a variety of other items, especially when preferred prey has declined due to drought or seasonal conditions. O . . .

Three out of five wild populations and a laboratory- population of Indian meal moth, Plodia interpunctella (Hubner), were found resistant to malathion. A malathion-susceptible Indian meal moth population, stressed with malathion, showed a 110-fo . . .

The subject of this study, Peromyscus boylei (the brush mouse), is found from "Honduras northward to Oregon and Utah and eastward to the Ozark Mountains" (Hooper, 1968: 50). In California, it is found characteristically in the Upper Sonoran life zo . . .

The fitness of an organism depends on its energetics, which includes both the amount of energy entering the individual and the distribution of energy within the individual. The present thesis examined the energetics of a scleractinian coral during and . . .

Gastrulation is a fundamental process that mediates formation of ectoderm, mesoderm and endoderm in most animals. Revealing the mechanism of gastrulation will provide a better understanding of embryonic development. Due to its transparency, simplicity . . .

The differentiated state of somatic cells can be reprogrammed to induced pluripotent stem cells (iPSCs), leading to the reactivation of the inactive X chromosome (Xi) of female differentiated cells in the mouse. In somatic cells, the Xi is very stable . . .

Microarray data can be used to derive an understanding of the relationships between the genes involved in various biological systems of an organism, given the availability of web applications and databases of gene expression measurements from the comp . . .

Sarcoma 180, a mouse ascites tumor, was examined ultrastructurally using transmission electron microscopy. Its general fine structure, and the cell surface interactions occurring as a result of agglutination were examined. Three types of agglutinins w . . .

Stem cells are necessary for proper development, tissue homeostasis and regeneration while dysregulation of their activity leads to diseases such as diabetes, neurodegeneration and cancer. Yet, the molecular and cellular mechanisms that drive stem cel . . .

Various stages of developing sea urchin embryos were fixed and fractured open in order to study the structural nature of the blastocoel. Fine structural analyses revealed a voluminous, fibrillar, extracellular matrix (ECM) composed of collagen-like fi . . .