Physical Sciences and Mathematics Commons^™

Movements, Habitat Use, And Abundance Of Lake Sturgeon (Acipenser Fulvescens) In Lake Champlain, Lisa K. Izzo

Graduate College Dissertations and Theses

Lake sturgeon (Acipenser fulvescens) in Lake Champlain were listed as endangered in 1972. Significant gaps exist in understanding lake sturgeon in the system as well as the methods needed to properly monitor and assess them. My research had three main goals: (1) investigate movements and habitat use of lake sturgeon in the Lake Champlain basin, (2) develop a method to estimate lake sturgeon abundance using sonar technology, and (3) test an alternative method for aging lake sturgeon.

One of the primary information gaps for lake sturgeon in Lake Champlain is an understanding of the movements and habitat use of multiple …

Hydrodynamic Modeling Of Lake Champlain: Current Resources, Major Gaps, Mae Kate Campbell, Julianna White

Lake Champlain Sea Grant Institute

Hydrodynamic models are computer-based programs designed to simulate processes and movements in water bodies. Scientists and policymakers use the robust information produced by hydrodynamic models to improve our understanding and develop policies for the protection and future management of water bodies. Current environmental issues in Lake Champlain that are or could be informed by hydrodynamic models include excess nutrients, changing temperature dynamics, flooding, harmful algae blooms, pathogens, contaminants, and invasive species. Existing hydrodynamic models are currently used to forecast flood risk and to determine how seasonal water current and nutrient dynamics affect the occurrence of harmful algae blooms, among other …

Seasonal Water Column Dynamics Exert Strong Control On The Chemical Partitioning Of Benthic Phosphorus Pools Of Shallow Eutrophic Freshwater Systems, Meagan Leduc

Graduate College Dissertations and Theses

In shallow lake systems, phosphorus (P) availability to cyanobacteria populations is often controlled by the release (internal loading) or sequestration of sediment P. This study provides novel insight into the feedbacks between the water column and benthic P pools across multiple time scales and explain how these dynamics influence chemical partitioning of P in lake sediment. Phosphorus partitioning in seasonal sediment core time series collected from a shallow eutrophic bay of Lake Champlain were quantified with SEDEX and enzyme hydrolysis selective extraction schemes. Time series extraction data were interpreted with concurrent water column physical and biogeochemical monitoring data to examine …

Evaluation Of Mysis Partial Diel Vertical Migration, Brian Patrick O'Malley

Graduate College Dissertations and Theses

Mass animal migrations represent large movements of biomass, energy, and nutrients with predictable patterns and important ecosystem-level consequences. Diel vertical migration (DVM) in aquatic systems, the daily movement of organisms from deeper depths during the day to shallower depths in the water column at night, is widespread in freshwater and marine systems. Recent studies, however, suggest partial migration behavior, whereby only some portion of a population migrates, is the rule rather than the exception in a range of migratory fauna, including those that undergo DVM. Hypotheses to explain why partial migrations occur complicate traditional views on DVM and challenge conventional …

Genetic And Demographic Consequences Of Lake And River Habitat Fragmentation On Fishes In Vermont, Peter T. Euclide

Graduate College Dissertations and Theses

Globally, habitat fragmentation has had a major impact on the conservation and management of many species and is one of the primary causes of species extinction. Habitat fragmentation is loosely defined as a process in which a continuous habitat is reduced to smaller, disconnected patches as the result of habitat loss, restriction of migration or the construction of barriers to movement. Aquatic systems are particularly vulnerable to habitat fragmentation, and today an estimated 48% of rivers are fragmented worldwide. My dissertation evaluates how habitat fragmentation has influenced the populations of four different species of fish in the Lake Champlain basin. …

Early Feeding In Lake Trout Fry (Salvelinus Namaycush) As A Mechanism For Ameliorating Thiamine Deficiency Complex, Carrie L. Kozel

Graduate College Dissertations and Theses

Recruitment failure of lake trout (Salvelinus namaycush) in the Great Lakes has been attributed in part to the consumption of alewife (Alosa pseudoharengus) by adult lake trout, leading to Thiamine Deficiency Complex (TDC) and early mortality in fry. The current understanding of thiamine deficiency in lake trout fry is based on information from culture and hatchery settings, which do not represent conditions fry experience in the wild and may influence the occurrence of TDC. In the wild, lake trout fry have access to zooplankton immediately following hatching; previous studies found that wild fry begin feeding before complete yolk-sac absorption. However, …

A Framework For Estimating Nutrient And Sediment Loads That Leverages The Temporal Variability Embedded In Water Monitoring Data, Baxter G. Miatke

Graduate College Dissertations and Theses

Rivers deliver significant macronutrients and sediments to lakes that can vary substantially throughout the year. These nutrient and sediment loadings, exacerbated by winter and spring runoff, impact aquatic ecosystem productivity and drive the formation of harmful algae blooms. The source, extent and magnitude of nutrient and sediment loading can vary drastically due to extreme weather events and hydrologic processes, such as snowmelt or high flow storm events, that dominate during a particular time period, making the temporal component (i.e., time over which the loading is estimated) critical for accurate forecasts. In this work, we developed a data-driven framework that leverages …

Double-Crested Cormorant And Ring-Billed Gull Damage Management On Lake Champlain: Are Basin-Wide Objectives Achievable?, Richard Chipman, Dennis Slate, Larry Garland, David Capen

Eighth Eastern Wildlife Damage Management Conference (1997)

Ring-billed gulls ( Larus delewarensis) and double-crested cormorants ( Phalacrocorx auritus) have nested on Lake Champlain since 1949 and 1982, respectively. Recent increases in cormorant nesting populations and pioneering activities of both species to previously uncolonized islands have resulted in impacts related to accumulation of bird guano and interspecific competition with less common species. Of primary concern are: decreases in wildlife and plant diversity on islands; reduced aesthetics and property values of island associated with the loss of trees; and predation or competition for nesting space with other species such as the state-endangered common tern (Sterna hirundo …

Stratigraphy And Structure At The Southern End Of Lake Champlain In Benson, Vermont, Jennifer L. Granducci

Geology Theses and Dissertations

Detailed mapping and structural investigations in an area bound to the west by the Grenvillian basement of the Adirondack Mountains and to the east by the allochthonous slates of the Taconic Mountains led to the distinction of a Western Undeformed Zone and an Eastern Deformed Zone. The former is composed of the gently east-dipping shelf sequence of upper Cambrian to lower Ordovician clastics and carbonates which unconformably overlie the Precambrian basement. The latter is characterized by lower to middle Ordovician carbonates, striking roughly north-south and dipping predominantly to the east, which are overlain by well-cleaved shales and slates. The stratigraphic …