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Ecological Consequences Of Lost Anadromous Forage Fish In Freshwater Ecosystems, Steven R. Mattocks

Masters Theses

Beginning in the early 1600s, dam construction in New England obstructed anadromous fish access to spawning grounds during migration. As a result, anadromous forage fish populations have declined, which has impacted freshwater, marine, and terrestrial ecosystems. To determine the impacts of dams on anadromous forage fish and freshwater ecosystems, I used historical and current data to estimate population changes in alewives (Alosa pseudoharengus) from 1600-1900. A significant reduction in spawning habitat occurred in New England as a result of 1,642 dams constructed between 1600 and 1900, resulting in 14.8% and 16.6% lake and stream habitat remaining by 1900, …

River Herring Conservation In Freshwater: Investigating Fish Reproductive Success And The Educational Value Of Citizen Monitoring Programs, Meghna Marjadi

Masters Theses

Over the last century anadromous alewife (Alosa psuedoharengus) and blueback herring (Alosa aestivalis), collectively called river herring, suffered drastic declines throughout their range from Newfoundland (Canada) to North Carolina (USA). A 2011 petition to include river herring in the Endangered Species Act (ESA) was rejected, partly due to inadequate information towards identifying coast-wide population status. Additionally, knowledge gaps were identified with basic ecology of the river herring life cycle in freshwater, including species reproductive strategies. In Chapter 2, I investigated how body size, spawning arrival time, and sex influence river herring reproductive success. I collaborated with …

Factors Affecting Habitat Quality For Wintering Wood Thrushes In A Coffee Growing Region In Honduras, Brett A. Bailey

Masters Theses

Amongst the diversity of taxa that occur in the Neotropics, 200 migratory bird species that breed in temperate North America can be found. Many of these populations have seen significant declines since the 1960s. The Wood Thrush, Hylocichla mustelina, is one such species. Shade coffee and other agroforestry practices show potential for benefiting migratory species, but the quality of coffee habitat and optimal habitat characteristics for Wood Thrushes remain unknown.

I surveyed a spatially complex, agricultural landscape in Honduras outside the recognized winter range of the Wood Thrush and radio-tagged 46 individuals within rustic coffee farms during the winters …

Improving Aedes Mosquito Surveillance And La Crosse Virus Screening In Eastern Tennessee, Cassandra Urquhart

Masters Theses

La Crosse virus (LACV), transmitted by infected Aedes triseriatus, Ae. albopictus, and Ae. japonicus mosquitoes is the leading cause of pediatric arboviral encephalitis. Severe cases of LAC encephalitis occur in individuals 16-years-old or younger and may cause permanent neurological damage or fatality. No vaccines exist making mosquito control and disease prevention crucial to public health. Effective screening and surveillance practices are key components to these goals. While a number of standard mosquito surveillance methods exist, continuous testing and improved understanding of vector biology to determine the best ways to implement these methods is important. Additionally, the current standard …

Spatial Ecology Of Great Barracuda (Sphyraena Barracuda) Around Buck Island Reef National Monument, St. Croix, U.S.V.I., Sarah L. Becker

Masters Theses

Marine protected areas (MPAs) are increasing in popularity as a tool to manage fish stocks through conservation of entire habitats and fish assemblages. Quantifying the habitat use, site fidelity, and movement patterns of marine species is vital to this method of marine spatial planning. The success of these protected areas requires that sufficient habitat is guarded against fishing pressure. For large animals, which often have correspondingly large home range areas, protecting an entire home range can be logistically challenging. For MPAs to successfully protect large top predator species, it is important to understand what areas of a home range are …

Trophic Relationships Among Caribou Calf Predators In Newfoundland, Chris Zieminski

Masters Theses

Using specially trained scat detection dogs we located fecal samples from black bear (Ursus americanus) and coyote (Canis latrans) throughout three study areas in Newfoundland, Canada, to describe these predators diet. Our sampling efforts were designed around seasons which were important to woodland caribou (Rangifer tarandus caribou) calving and resource use. We identified hairs microscopically to prey species and grouped other remains to facilitate our analysis. Bear exhibited an omnivorous diet throughout the study areas, ecological seasons and inside and outside the caribou calving grounds while coyote were limited to caribou, moose and snowshoe …

Modeling Historical And Future Range Of Variability Scenarios In The Yuba River Watershed, Tahoe National Forest, California, Maritza Mallek

Masters Theses

In California's northern Sierra Nevada mountains, the fire-dependent processes of forest ecosystems have been interrupted and altered by human land use and fire suppression. U.S. Forest Service policy directs land managers to plan for a future that includes multiple use and the restoration of resilient ecosystems. Planning decisions are to be informed by an analysis of the range of variability of ecological processes at multiple scales. Current climate trends in the northern Sierra are of increasing temperatures, increased precipitation, and earlier snowmelt, as well as changes to the frequency and duration of drought. These climate changes have and continue to …

Estimating Avian Populations With Passive Acoustic Technology And Song Behavior, Stephanie C. Prevost

Masters Theses

The need for improvements in avian wildlife monitoring efficiency, accuracy, and scope has led to use of new technologies such as autonomous recording units (ARUs). As a monitoring tool, passive acoustic recording has numerous benefits, but it is still limited to use in human-accessible areas. There is also need for monitoring technologies in areas that are inaccessible. Military installations, which host a disproportionately large number of threatened, endangered, and at-risk species compared to other federal lands, pose the accessibility problem with sizeable impact areas that are too hazardous for humans to access. This thesis introduces the Balloon Aerial Recording System …

Using Phylogenetics To Understand The Evolutionary Relationships Of Hibiscus Section Furcaria, Whitaker Matthew Hoskins

Masters Theses

Neopolyploids constitute at least 35% of known species of angiosperms, and because polyploidization is a pertinent process in plant diversification and domestication, it is a thriving field of study. Hibiscus section Furcaria includes several groups of polyploids in addition to ten known diploid species. In previous studies genome groups for Hibiscus section Furcaria were determined through artificial hybridization experiments and patterns of biogeography were elucidated based on the distribution of diploids and polyploids. For instance, the Australian hexaploids contain 3 genomes (designated G, J, and V) and are thought to have developed from a polyploidization event between an African diploid …

Urbanization Impacts On Land Snail Community Composition, Mackenzie N. Hodges

Masters Theses

Urbanization has tremendous impacts on most native species. Urban ecosystems are becoming increasingly prevalent, while urban ecology is a relatively underdeveloped field. This is especially true for terrestrial mollusks, which are a surprisingly understudied organism. Due to their low mobility and dispersal potential, land snails are valuable indicators of ecosystem disturbance. For this study, land snails were collected in 54 city parks along an urban gradient to understand influences of urbanization on snail communities. Sampled parks include small extensively landscaped downtown parks, neighborhood and community parks, district parks, and large nature parks, each with variable vegetation, soil characteristics, disturbance regimes, …

Variations In The Invertebrate Communities Of Wild Cape Cod Cranberry Bogs, Barbara Wagner

Masters Theses

As a species domesticated only in the last century, agricultural cranberry plants (Vaccinium macrocarpon) remain little removed from their wild relatives. Thus, it is a potential model species for studies of the earliest stages of domestication; however, there is little available quantitative information on its wild population biology and ecology. As such information is vital to studies of the ecological changes occurring during domestication, the purpose of this study was to consolidate the relevant knowledge available and conduct a preliminary search for patterns in the invertebrate communities of wild bogs. The alpha diversity was found to be greater …

Population Genetic Analysis Of Atlantic Horseshoe Crabs (Limulus Polyphemus) In Coastal Massachusetts., Katherine T. Johnson

Masters Theses

Atlantic horseshoe crabs (Limulus polyphemus) have endured decades of intense harvest pressure. Genetics studies have shown evidence of distinct sub-groups spanning the coast, although few fine-scale studies have been done to delineate these groups on a local level. Massachusetts lies directly between two of these sub-groups. With documented differences in prosomal widths of horseshoe crabs from either side of Cape Cod, it is possible that Cape Cod is a barrier to gene flow and that there are two distinct genetic groups within Massachusetts. Regulations currently consider all horseshoe crabs to be of one stock. I examined 6 microsatellite …

Effects Of Habitat Alteration On Ecomorphology Of Fish Communities In A Restored Stream, Carl Anthony Favata

Masters Theses

Decades of anthropogenic pressure have devastated lotic ecosystems across the riverscapes of North America, resulting in degradation of critical habitat and contributing to sharp declines in biotic integrity. In response, local stream restoration projects have increased in frequency. However, little effort has been allocated to monitoring and project success has been limited. In addition, restoration projects typically focus on ecological effects above the population-level, while relationships with physiological processes are seldom assessed. Lessons from the long-term restoration and ecological monitoring of Kickapoo Creek highlight some of the complex dynamics driving reach-scale restoration projects. Following instream restoration, I predicted that alterations …

Demographics And Parasites Of Spotted Bass In The Wabash River, Evan C. Boone

Masters Theses

Spotted Bass Micropterus punctulatus Rafinesque are a popular sport fish primarily found in the streams and reservoirs of the south. The Wabash River, a large tributary of the Ohio River, contains a naturally reproducing population on the northern boundary of their range. Currently, the lower Wabash River is monitored using two different sampling designs, the Long Term Electrofishing Program monitors community assemblages using stratified random sampling whereas the Illinois Department of Natural Resources uses a fixed sampling design. Due to the wide distribution but low abundance of Spotted Bass throughout this drainage, captures from each design were compared to assess …

Successional Changes In Leaf Nutrient Concentrations Of Woody And Herbaceous Species, Daniel Walter Kuchta

Masters Theses

Leaf nutrient concentrations are an example of a functional trait, a trait that can be used to understand community dynamics by observing how plants interact with their environment. I explored how leaf nutrient concentrations were affected over successional time by environmental changes. The majority of prior research on functional traits focuses on either woody or herbaceous species, but not both life forms simultaneously. To address this, I also explored the successional changes to leaf nutrient concentrations, separating the plant community into woody and herbaceous species.

Healthy, mature leaves were taken from 122 taxa of woody and herbaceous species in a …

Diel And Seasonal Patterns Of Channel Catfish Movement And Habitat Use In The Lower Wabash River, Hanna Gibbs Kruckman

Masters Theses

Channel catfish Ictalurus punctatus are commonly found throughout the Mississippi River basin and support commercial and recreational fisheries in many large river systems. Understanding population demographics as well as movement patterns and habitat usage can provide a more holistic approach to species management and conservation. Within a 16-km stretch of the lower Wabash River, 27 channel catfish were implanted with acoustic transmitters to monitor fine scale movement and habitat use from September 2014 through April 2016. Channel catfish were located using active tracking during two types of tracking events. Site tracking occurred only during daylight hours and diel tracking monitored …

Low-Head Dams On Habitat, Fish Functional Guilds And Genetic Structuring In A Midwestern River System, Shannon Cassandra Frary Smith

Masters Theses

The natural flow regime of the majority of rivers in the United States has been altered by anthropogenic structures. This loss of connectivity plays a strong role in shaping river ecosystems by altering physical habitat characteristics and shaping fish community assemblages. Although the impacts of large dams on river systems are well documented and often easy to observe, there are fewer studies on the effects of smaller low-head dams. Additionally, the influences of low-head dams on the genetic structuring of small-bodied riverine fishes have yet to be fully explored. I assessed the effects of two low-head dams on the Vermilion …

Sampling Efficiency, Population Characteristics, And Potential Impacts Of Harvest Regulations On Three Riverine Species Of Catfish, Zachary Adam Mitchell

Masters Theses

No abstract provided.

Quantifying Bat Detection Survey Methods And Activity Patterns, Tara C. Hohoff

Masters Theses

Bats have an astonishing diversity and provide vital ecosystem services in an array of different niches. In North America, most species of bats are insectivores and tend to be frequently overlooked for their important ecosystem role providing insect control. As bat populations have declined in recent years, farmers, land managers, conservationists, and bat enthusiasts have wondered what we can do to protect our local bat populations. As a first step, we need to develop methods that more effectively survey for rare species of bats. By performing inefficient surveys, we are doing a disservice to our funding agencies providing misinformation that …

Stopover Ecology Of Neotropical Migratory Songbirds In The Northern Yucatan Peninsula, Mexico, Lauren E. Solomon

Masters Theses

Chapter I. Full-service hotels, convenience stores or fire escapes? Evaluating function of stopover sites for Neotropical migrants in the northern Yucatan Peninsula

Nearctic-Neotropical migratory songbirds incur the highest mortality rates during their annual migrations. Migratory songbirds use a network of stopover sites to rest, refuel, or seek refuge during times of poor weather conditions; and the time and energy expended at these sites exceeds that of migratory flight. In order to conserve stopover sites with the highest value to Neotropical migrants, a conceptual framework was developed to classify stop over sites into three functional categories based on their function for …