Physical Sciences and Mathematics Commons^™

Analysis Of The Spatial Dynamics Of The American Lobster (Homarus Americanus) Fishery Along The Coast Of Maine, Kevin M. Scheirer

Electronic Theses and Dissertations

The American lobster (Homarus americanus) supports the most valuable commercial fishery in the northeastern United States, thus the fishery is critical to Maine's economy. No systematic study has been done to collect information about, identify, and quantify the spatial dynamics of the Maine lobster fishery. This project helps to provide a better understanding of Maine's lobster fishery dynamics, and it will aid f'iture efforts to improve the stock assessment of Maine's lobster fishery. The analysis consists of three distinct parts: (1) comparison of data collected by two separate fishery dependent sampling programs; (2) spatial analysis of electronic logbook data; and …

Specific Dynamic Action, Growth And Development In Larval Atlantic Cod, Gadus Morhua, Jessica A. Geubtner

Electronic Theses and Dissertations

The larval stage of marine fish is a period of rapid growth and development. Atlantic cod (Gadus morhua) are approximately 4-5 rnm in length upon hatch and feed endogenously from their yolk sac for the first week. After this time, larval cod must successfully capture live prey to survive and to fuel high growth rates of greater than 10%d". Previous studies have found that during exogenous feeding and at growth rates greater than 8%d1 larvae experience what appears to be cost free growth, where mass specific metabolic rate does not decrease with increasing mass. Due to size and condition constraints …

The Role Of Larval Thermal Tolerance In The Distribution Of Blue Mussel Species Within The Gulf Of Maine, Susan J. Limbeck

Electronic Theses and Dissertations

Two species of blue mussel, Myrilus edulis and Myrilus trossulus, are sympatric throughout much of the Canadian Maritime Provinces and into the Gulf of Maine. While the distribution of M edulis extends south to the Mid-Atlantic, that of M. trossulus ends abruptly in the Gulf of Maine. I have hypothesized that these differences in adult distribution are the result of species-specific variation in larval thermal tolerances. Previously, it has been shown that when reared at 20 OC, from 36 hour post-fertilization through settlement, M. trossulus had significantly higher mortality rates than M. edulis. This study examined whether species-specific differences in …

An Investigation Of The Cumulative Impacts Of Shrimp Trawling On Mud Bottom Fishing Grounds In The Gulf Of Maine: Effects On Habitat And Macrofaunal Community Structure, Anne W. Simpson

Electronic Theses and Dissertations

Despite the widespread occurrence of trawl fisheries on mud-bottoms, there is limited knowledge concerning the effects of trawling induced disturbance on these habitats and their resident macrofaunal communities. I investigated the cumulative impacts of seasonal commercial shrimp trawling on infaunal habitat and macrofaunal community structure on two mud-bottom fishing grounds in the Gulf of Maine from June 2000 - December 2001. One fishing ground located near the Outer Pumpkin Ledges (Pumpkin) experienced trawling activity during the 2000-2001 fishing season. In contrast, the other fishing ground near Monhegan Island was not trawled during the same period because shrimp abundances were low. …

Resilience Of Green Sea Urchin (Strongylocentrotus Droebachiensis) Populations Following Fishing Mortality: Marine Protected Areas, Alternate Stable States, And Larval Ecology, John Vavrinec Iii

Electronic Theses and Dissertations

The green sea urchin Strongylocentrotus droebachiensis has been aggressively fished in Maine since 1986 resulting in severe population declines throughout portions of the state. This research used Marine Protected Areas (MPAs) to evaluate the potential for recovery in depleted sea urchin populations. It was necessary to not only look at the direct impacts of the MPAs, but also at larval transport / supply and community interactions to gain a better understanding of the system. We found that MPAs in the Gulf of ~a!ne were of varied utility to restoring depleted sea urchin populations depending on location and community structure. MPAs …

Hydroperiod Of Wetlands And Reproduction In Wood Frogs (Rana Sylvatica) And Spotted Salamanders (Ambystoma Maculatum), Mary Beth Kolozsvary

Electronic Theses and Dissertations

Many amphibians rely on wetlands for reproduction and the differential distribution of amphibian species along a gradient of wetland permanence is striking, yet not absolute. Wood frogs (Rana sylvatica) and spotted salamanders (Ambystoma maculatum) are thought to rely on seasonal wetlands for greatest breeding success, but there is little documentation of their reliance on these or other habitats. In my first chapter, I studied these species in wetlands across a hydrologic gradient from seasonal wetlands of short flood duration to permanently flooded sites. My results indicate that wood frogs have greatest reproductive effort and success in …

Geographic Variation In The Morphology Of Crotalus Horridus (Serpentes: Viperidae), John Robert Allsteadt

Biological Sciences Theses & Dissertations

The Timber Rattlesnake (Crotalus horridus) occurs in discontinuous populations throughout the eastern and central United States. The species exhibits high levels of polymorphism in morphological traits, especially in coloration and pattern. Previous studies recognized either distinct northern and southern subspecies or three regional morphs (northern, southern, and western), but conflicting data sets and limited geographic sampling of previous studies have left the relationships among those regional variants unclear. In this study, univariate and multivariate statistics, together with a geographic information system, were used to analyze geographic variation in 36 morphological characters recorded from 2,420 specimens of C. horridus …

Fluctuations In Chinook Salmon (Oncorhynchus Tshawytscha) Counts At Three Lower Columbia River Spawning Sites, Eric Michael Loomis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Several hypotheses were developed to explore the pronounced increase in Chinook salmon (Oncorhynchus tshawytscha) returning to spawning grounds at the Cowlitz, Kalama, and Lewis Rivers, three tributaries of the lower Columbia River. The study was conducted using data compiled over a ten-year span from 1991-2001. Preliminary indications are that trends in climate are linked to these increases, with the absence of El Niño events and fluctuations in winter precipitation as likely explanations of these phenomena. The unique nature of Chinook life cycles causes them to utilize a variety of habitats that require ideal conditions for maximum survival rates. Correlations between …

The Use Of Acoustics To Resolve Nightly Excursions Of Hyperbenthos, Heather U. Abello

Electronic Theses and Dissertations

Acoustic analysis of die1 vertical migration in the Darnariscotta River estuary, Maine, showed a fairly regular nightly increase in biovolume (mm3 m'3) of organisms in the water column, presumed to be due to emergence, the entry of hyperbenthic organisms into the water column. Timing of these events was significantly correlated with time of sunset and time of sunrise for more than 50% of the dates where emergence and re-entry could be identified, between June and October 2002. Emergence traps indicate that the mysid shrimp, Neomysis americana, is the predominant migrator. Daily fluctuations in irradiance influence the timing of emergence fiom …

Modeling Bird Species Occurrence In Current And Future Landscapes, Stephen Nicholas Matthews

Electronic Theses and Dissertations

With mounting evidence that global temperatures have increased significantly over the last century and the projections of greater changes in climate by the end of this century, understanding the potential consequences of these changes for species is essential to conservation efforts. Here I evaluate the potential response of birds to projected climate change by using regression tree analysis to create models of species distributions under current conditions from Breeding Bird Survey data and then project these models onto General Circulation Model (GCM) scenarios of global climate change. Before modeling species responses to climate change, I selected seventeen bird species to …

Population Dynamics And Spatial Analysis Of The Maine Green Sea Urchin (Strongylocentrotus Droebachiensis) Fishery, Robert C. Grabowski

Electronic Theses and Dissertations

Fisheries research on the green sea urchin in Maine has been limited despite its importance to the state's fishing industry. The objective of this thesis was to generate critical information for the management and monitoring of the Maine green sea urchin fishery. In particular there are three main areas of interest: (1) an investigation of biological reference points; (2) spatial analysis and biomass estimation, and (3) the development of a simulation framework approach to determine an optimal sampling strategy for the fishery-independent survey program. Biological reference points are markers conlrnonly used to monitor and manage fisheries. For the Maine sea …

Scope For Activity, Specific Dynamic Action And Growth In Early Juvenile Stages Of Atlantic Cod, Gadus Morhua, Sorren Lund Hansen

Electronic Theses and Dissertations

Growth rates of early life stages of Atlantic cod (Gadus morhua) are very high, but decline, as the fish grow larger. Little is know about the physiological processes that facilitate and regulate this growth pattern. In this study, feeding and swimming metabolism were measured in individual juvenile Atlantic cod (Gadus morhua) in order to investigate how energy are allocated to swimming and growth in fast growing stages of fishes. Metabolic rates were measured by the means of oxygen consumption using two "Brett-type" respirometers. The metabolic measurements were repeated several times in individual juvenile Atlantic cod with a wet body mass …

Lipid Solubilization By Marine Benthic Invertebrates, Ian M. Voparil

Electronic Theses and Dissertations

This work characterized the size of lipoidal colloids in benthic invertebrates' guts, using contact angle dilutions and imaging the fluorescence of the hydrophobic probe Nile Red. Deposit feeders and Nereis virens ingesting sediment were found to have micelles rather than emulsions in the gut. Gut fluids from Arenicola manna (a deposit-feeding polychaete) readily formed emulsions when incubated with mussel meat (Mytilus edulis; 80 g-mussel L"-gut fluid), suggesting that micelles form due to a paucity of emulsifying lipids in the gut. Lipid tracer contained in emulsion droplets was twice as likely to be captured by sediment than was tracer in micelles. …

Modeling Habitat Quality For American Martens In Western Newfoundland, Canada, William A. Adair

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The "Den Mother" marten habitat quality models were created to provide insight into American marten habitat selection behavior and to promote the recovery of the Newfoundland marten (Martes americana atrata) population. Although these objectives are typical of most wildlife habitat modeling projects, the marten's idiosyncratic habitat ecology and apparently intractable conflicts associated with timber harvesting motivated a unique, process-oriented approach to appraising landscapes. The Den Mother models used optimal decision-making principles to synthesize critical resources (den sites and foraging opportunities) and constraints (adverse thermal situations and exposure to predations) into a single hierarchical framework. The resulting spatially explicit, …

Breeding Bird Communities Of Major Mainland Rivers Of Southeastern Alaska, Jim A. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Because of the scarcity of information for bird communities at the major mainland rivers of southeastern Alaska, the main objective of this study was to provide baseline information including distribution, status, and habitat associations of breeding birds.

I conducted a meta-analysis of all known reports (including the current study) conducted at major mainland rivers during the breeding season. I described bird species composition, distribution, abundance estimates, status, habitat associations, and guild membership for all birds recorded at 11 major mainland rivers. Based on incidental observations, 170 species were recorded by all studies. Of these, 134 species were known or suspected …

An Analysis Of Materials Suitable For Use As A Pitfall Trap In A Desert Environment, R. Renee Brown

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to identify a type of pitfall trap container that can withstand the temperature extremes of the Mojave Desert in which the terrestrial, or above ground, drift fence with pitfall traps will be utilized for trapping reptiles. A pitfall trap is a container, such as a plastic bucket with a plastic lid, that is buried in the ground up to the lip of the bucket and used to catch small ground dwelling fauna that fall into the trap. Many different pitfall trap materials have been utilized in the trapping of small ground-dwelling fauna. Plastic has …

A System Dynamics Investigation Of Genetic Drift And Translocation In The Red-Cockaded Woodpecker Metapopulation, Jason E. Yates

Theses and Dissertations

The red-cockaded woodpecker (Picoides borealis) is classified under the Endangered Species Act of 1973 as an endangered species As such, the red-cockaded woodpecker (RCW) is afforded strict protection in an effort to return the RCW population to a self-sustainable level. Endemic to southeastern United States mature pine forests, the presence of the RCW impacts the operations of many Department of Defense (DoD) installations. A particular challenge in sustaining what are often small populations of RCW at these locations is the loss of genetic variation due to genetic drift. The optimal method for mitigating such loss is through the artificial immigration, …

Analysis Of Prey Selection In Black Skimmer, Rynchops Niger, Adults And Chicks Using Continuous Video Monitoring, Renae Joyce Held

Dissertations, Theses, and Masters Projects

No abstract provided.

Use Of Ponds And Lakes By Resident Canada Geese, Phillip D. West

Dissertations, Theses, and Masters Projects

No abstract provided.

Biology Of Mated Triploid Crassostrea Ariakensis In Multiple Environments: Gametogenesis, Sex Ratio, Disease Prevalence, And Reversion, Alan J. Erskine

Dissertations, Theses, and Masters Projects

No abstract provided.

Historical Diet Analysis Of Loggerhead (Caretta Caretta) And Kemp's Ridley (Lepidochelys Kempi) Sea Turtles In Virginia, Erin E. Seney

Dissertations, Theses, and Masters Projects

The Chesapeake Bay and coastal waters of Virginia, U.S.A. serve as foraging grounds for loggerhead (Caretta caretta) and Kemp’s ridley (Lepidochelys kempi) sea turtles from approximately May to October each year. Both loggerheads and Kemp’s ridleys are known to feed primarily on benthic invertebrates as juveniles and adults, but specific prey preferences vary between geographic regions. The Virginia Institute of Marine Science Sea Turtle Program has collected diet data and gut samples from stranded and incidentally caught sea turtles in Virginia since 1979. Examination of turtles that stranded in Virginia during the late 1970s and early 1980s indicated that loggerheads …

Diet Of The Sandbar Shark, Carcharhinus Plumbeus, In Chesapeake Bay And Adjacent Waters, Julia K. Ellis

Dissertations, Theses, and Masters Projects

The sandbar shark, Carcharhinus plumbeus, is the most abundant large coastal shark in the temperate and tropical waters of the northwest Atlantic Ocean. The Chesapeake Bay, Virginia and adjacent waters serve as a nursery ground for C. plumbeus as well as many other fauna. Characterizing the diet of a higher trophic level predator such as the sandbar shark sheds light on a small portion of the temporally and spatially complex food web in the Bay. This study describes the diet of the sandbar shark, highlighting differences in diet within various portions of the nursery area, as well as ontogenetic changes …

A Genetic Analysis Of The Intraspecific Relationships Of Tropical Marine Shorefishes Common To Bermuda And The Southeastern Atlantic Coast Of The United States, Kelly R. Johnson

Dissertations, Theses, and Masters Projects

No abstract provided.

Distribution, Abundance, And Home Range Of The Whip-Poor-Will (Caprimulgus Vociferus) In A Managed Forest Landscape, Michael Daniel Wilson

Dissertations, Theses, and Masters Projects

No abstract provided.