Terrestrial and Aquatic Ecology Commons^™

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 …

Ectomycorrhizal Fungal Community Assembly On Seedlings Of A Neotropical Monodominant Tree, Carolyn Delevich

Cal Poly Humboldt theses and projects

Formation of ectomycorrhizae may facilitate early seedling survival of ectomycorrhizal tree species due to enhanced nutrient acquisition. This could be especially important in heavily shaded understories of tropical monodominant forests where host plant photosynthetic capacity is limited. Little information is available on ectomycorrhizal (ECM) fungal colonization or community development of monodominant seedling cohorts, which have high survival rates. Following a 2016 mast seeding event, we sequentially measured percent colonization and species composition of ECM fungi on live and recently dead seedlings of the tropical monodominant tree Dicymbe corymbosa. We also compared seedling ECM fungi to those of nearby adult …

Role Of Managed Marine Areas On The Diversity And Individual Responses Of Rocky Intertidal Shore Grazers In Central Chile, Kathy Liu

Scripps Senior Theses

Many different types of marine benthic herbivores or “grazers” inhabit coastal intertidal zones and play a crucial role in inter- and shallow subtidal ecosystems. Chile has one of the most diverse intertidal zones, but many intertidal grazers are exploited for human consumption. Marine protected areas (MPAs) and marine management and exploitation areas (MEAs) are promising tools for Chile to combat over exploitation of these grazer and other marine resources. This study surveyed the impact of sites with contrasting management on the diversity and abundance of all intertidal grazers and their impact on the size frequency and shell length-body weight allometry …

Spatial And Temporal Distributions Of Larval Clupeid Fishes In A Tidal Freshwater Marsh Complex, Philip Reid Anderson

Theses and Dissertations

Tidal freshwater wetlands provide valuable ecosystem services such as nutrient cycling, coastal flood control, and reproductive habitat for early life stages of economically and ecologically important fishes. The nutrient rich environments that tidal freshwater wetlands occur in support high levels of primary productivity of phytoplankton and vegetation that provide essential reproductive habitat for anadromous clupeid fishes (Alosa spp., Brevoortia tyrannus) in Chesapeake Bay tributaries. Seasonal retention of clupeid eggs and larvae within tidal freshwater habitats may enhance early growth, survival, and year class strength. The primary goal of the present study was to characterize the relative importance of …

Prairie Dogs And Livestock In Rangeland Systems: Balancing Biodiversity And Production In The Northern Mixed-Grass Prairie, Jameson Robert Brennan

Electronic Theses and Dissertations

A major constraint of beef production within the Standing Rock Reservation has been identified as a reduction in rangeland quality due in large part to wide-scale colonization by black-tailed prairie dogs (Cynomys ludovicianus). The desire exists within the community to design a holistic framework which incorporates livestock management with the goal of increasing production and rangeland health while still maintaining increased diversity associated with prairie dogs. Prairie dogs reduce the carrying capacity of cattle on rangelands by up to 50% on occupied hectares through direct consumption of vegetation and waste due to clipping to improve detection of predators. Livestock stocking …

Assessment Of Quantity And Quality Of Microplastics In The Sediments, Waters, Oysters, And Selected Fish Species In Key Sites Along The Bombong Estuary And The Coastal Waters Of Ticalan In San Juan, Batangas, Emilyn Q. Espiritu, Sophia Angeli Sn Dayrit, Annabel Soledad O. Coronel, Natasha Sophia C. Paz, Pilar Isabel L. Ronquillo, Virgil Christian G. Castillo, Erwin P. Enriquez

Chemistry Faculty Publications

Microplastics (or MPs; < 5 mm in size) pollution is largely unstudied in the Philippines. From an environmental sustainability standpoint, it is important to understand the characteristics, abundance, and environmental fate of plastic debris of various sizes, and these include microplastics that are not more easily and readily detected. In this study, we assessed the extent of microplastics contamination in the sediments, waters, oysters, and selected fishes found in the rivers and coastal areas of Ticalan, Batangas, which were identified from water quality parameters as Class C and CS, respectively. The microplastics were extracted from these samples by chemical digestion of the matrix, series of filtration, and separation by flotation through a density gradient to finally isolate the microplastics which were not dissolved by chemical digestion. The isolated samples were imaged by optical microscopy and characterized based on their descriptive attributes. The results showed the presence of microplastics in all the samples tested, which were found mostly in the form of filaments, fragments, films, and pellets – with most showing weathered, degraded, or angular and irregular surfaces. Identification was done through spectral matching of the Fourier transform infrared spectra of isolated fragments with that of known plastics, although identification in some cases is made uncertain by possibility of degradation of the plastics in the environment. The majority of the isolates showed signature absorption bands of the C-H stretching vibrations of polyethylene-based plastics.

Gateways-Nd: Building The Institutional Infrastructure Towards Viable Postsecondary Stem Education Reform, J.M.D. Motschenbacher, M. Vosen Callens, J. Nyachwaya, E. Berg, J. Ladbury, R. Reichenbach, P. Kelter

School of Natural Resources: Documents and Reviews

No abstract provided.

Exploration Of Sonic Hedgehog Gene Expression In Fathead Minnows (Pimephales Promelas), Brooke Renee Greiner

Undergraduate Honors Theses

Pollutants, as a result of wastewater treatments, have been shown to have negative impacts on aquatic ecosystems. To better understand the possible consequences caused by effluents on ecosystems, it is important to examine ecotoxicology data. One of the most commonly used species for water quality testing is the fathead minnow, Pimephales promelas. Ecotoxicology can then be taken one step further to understand the effects of pollutants on a molecular level. Previous research had identified effluents as causes for abnormal minnow fin morphology. In order to collect additional data on development, tanks with fathead minnows were placed at the Charleston …

The Diversity Of Terrestrial Mammals Surrounding Waterfall At Billy Barquedier National Park, Kelsey Johnson, Jason Apple

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Billy Barquedier is a National Park located in the Stann Creek district of Belize that contains Neotropical vegetation and wildlife. This study was performed to provide a baseline inventory and appearance frequency patterns of the terrestrial mammals located within Zone 1 of the park near a waterfall and to gain a greater understanding of the biodiversity and activity patterns of terrestrial mammals within the park. The methods included camera traps, small Sherman live traps, large live traps, and tracking methods. A non-random sampling method of placing camera traps and live traps on or near human-made or animal-made trails was used …

Riparian Resilience In The Face Of Interacting Disturbances: Understanding Complex Interactions Between Wildfire, Erosion, And Beaver (Castor Canadensis) In Grazed Dryland Riparian Systems Of Low Order Streams In North Central Washington State, Usa, Alexa Whipple

EWU Masters Thesis Collection

Riparian systems of low order streams in the western United States (US) provide critical ecosystem functions and services such as diverse habitat for numerous species, flood attenuation and essential water storage in water limited environments. These systems have experienced long term disturbance from anthropogenic activities including mining, timber harvest, livestock grazing and near extirpation of a keystone riparian species, Castor canadensis (North American beaver). However, increasing frequency of large-scale wildfires and climate change driven weather is altering the severity and scale of riparian disturbance, often shifting highly impacted streams to a stable degraded state, unable to store water or provide …

Home Range, Habitat Use And Thermal Ecology Of The Florida Box Turtle (Terrapene Bauri) On An Anthropogenic Island In Southwestern Florida, Christina Demetrio

Antioch University Dissertations & Theses

Limited information is available on the ecology of Terrapene bauri (Florida Box Turtle) in mangrove ecosystems. Radio-telemetry and iButton data loggers were used to study the home range, habitat use, and thermal ecology of ten Florida Box Turtles on an anthropogenic island in the mangrove-dominated region of southwestern Florida. The effects of weather variables on movement and activity were also examined. Home range analysis using Minimum Convex Polygons (MCP) and Kernel Density Estimates (KDE) determined an average home range size of 0.81 ha (MCP) and 2.32 ha (95% KDE). Box Turtles moved an average distance of 6.3 m per day …

Ranging And Behavior Of Black And Gold Howler Monkeys In Formosa, Argentina, Claire Rossi De Leon

Library Map Prize

Howler monkeys (Alouatta spp.) are known for their adaptability, allowing them to inhabit a large range of forest types and driving high levels of variation in ranging and behavioral patterns. I address a series of hypotheses relating these relationships: 1) If an energy minimizing lifestyle is an adaptation to eating high quantities of leaves, then howler groups that have a high proportion of leaves in their diet will occupy smaller home ranges, have shorter daily path lengths, and spend more time resting, 2) if temperature is the primary driver of high levels of resting, then howlers will conserve energy and …

Classification Of Native Vegetation Of Oregon - 2019, Jimmy Kagan, Rachel L. Brunner, John Christy

Institute for Natural Resources Publications

This classification is an update of the 2004 classification of native vegetation of Oregon by Kagan, Christy, Murray and Titus. As before, this classification lists the native plant associations known to occur in Oregon, and includes both successional and climax vegetation types that were part of the presettlement landscape of Oregon and can still be found in the state. It serves as an index to the diversity, distribution and relative rarity of the state's native plant associations, and as a guide to their literature. Published and unpublished reports supported by quantitative data were the primary sources for the classification. In …

Response Of Headwater Amphibians To Long-Term Logging Impacts And Assessing Potential For Restoration In Redwood National And State Parks, Alyssa Marquez

Cal Poly Humboldt theses and projects

The timescale of community response to disturbance varies drastically, and slow-recovering ecosystems such as coastal redwood forests may take hundreds of years to return to old-growth conditions post-logging. Few studies have quantified long-term (>50 years) impacts of disturbance on ecosystems, specifically aquatic ecosystems. This study provides evidence of the persistence of historical logging impacts 50 years post-logging through the comparison of headwater amphibian populations (occupancy and abundance) and stream characteristics using a control-treatment study with a logged watershed, Streelow Creek, as the treatment and a pristine old-growth watershed, Godwood Creek, as the control. The immediately adjacent old-growth watershed acts …

Autumn Roost Selection By Male Hoary Bats (Lasiurus Cinereus) In Northern California, Danielle (Skye) Salganek

Cal Poly Humboldt theses and projects

The hoary bat, Lasiurus cinereus, is a solitary bat that roosts in the foliage of trees throughout the western hemisphere. Roosts are subject to the ambient temperature of their surroundings, thus hoary bats undergo long-distance migrations between summer and winter ranges to avoid freezing temperatures. Habitat selection has been studied during the summer for maternal female hoary bats, but not during migration and winter. Autumn migration coincides with the hoary bat mating period and it has been proposed that male and female bats may rendezvous on migration paths. Individuals may select roosts in stopover locations that enhance fitness by providing …

Shade Trees Preserve Avian Insectivore Biodiversity On Coffee Farms In A Warming Climate, Sarah L. Schooler

Cal Poly Humboldt theses and projects

Coffee is an important export in many developing countries, with a global annual trade value of $100 billion. Climate change is projected to drastically reduce the area where coffee is able to be grown. Shade trees may mitigate the effects of climate change through temperature regulation for coffee growth, temperature regulation for pest control, and increase in pest-eating bird diversity. The impact of shade on bird diversity and microclimate on coffee farms has been studied extensively in the Neotropics, but there is a dearth of research in the Paleotropics. I examined the local effects of shade on bird presence and …

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 …

Modelling Stream Metabolism And Fish Biomass In Headwater Streams Of The Eastern Cascades Mountains, Zach Lessig

All Master's Theses

Headwater streams are important for the biological integrity of river systems because they represent most of the length of the hydrological network and control the downstream flow of energy and nutrients to larger river systems. Headwater streams are culturally and economically important because they, directly or indirectly, support recreationally important anadromous and resident fisheries. Managing fish in these systems often requires time-consuming population counts, but fish biomass might be related to overall stream productivity, which can be measured relatively easily using models to estimate stream metabolism. The goal of my study was to relate whole-stream metabolism to fish biomass in …

Changes In Walleye Fecundity And Egg Size Before, During, And After Rehabilitation Of The Red Lakes Fishery, Benjamin J. Miller, Benjamin D. Erb

Journal of Earth and Life Science

The Red Lakes in northern Minnesota experienced a major Walleye Sander vitreus fishery crash in the late 20th century, but has since recovered to record abundances and supports a major commercial and recreational fishery. Fecundity is an integral aspect of recruitment that can contribute greatly to the understanding of fishery population dynamics. To elucidate the effects of varying Walleye densities and exploitation rates on fecundity and egg size in years 1989 (overexploited fishery), 2004 (recovering fishery), and 2017 (recovered fishery), we analyzed linear models that related fecundity or egg size to morphological features for these three sampling periods. Walleyes were …

Goldeye Hidon Alosoides Calorimetry In Red Lake, Jesse Mendel

Journal of Earth and Life Science

Goldeye Hiodon alosoides are found across North America and are a relatively unstudied group of fish as they have had no economic value in the past. Ecologically speaking, these fish could have importance to the waters that they inhabit, as they are prey to fishes like Walleyes Sander vitreus, Northern Pike Esox lucius, and Muskellunge Esox masquinongy. These fish could potentially be vital to predatory fishes because of the amount of oil found in these fish, creating gram for gram more energy than compared to other consumable substances. The average energy density for all Goldeye was 6.73 …