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Full-Text Articles in Physical Sciences and Mathematics

Status Of The Major Oyster Diseases In Virginia 1993 A Summary Of The Annual Monitoring Program, Eugene M. Burreson, Lisa M. Ragone Calvo Aug 1994

Status Of The Major Oyster Diseases In Virginia 1993 A Summary Of The Annual Monitoring Program, Eugene M. Burreson, Lisa M. Ragone Calvo

Reports

No abstract provided.


Methods For The Comparison Of Timing Behavior Applied To The Pink Salmon Fisheries Of Prince William Sound, Alaska, Louis J. Rugolo Apr 1994

Methods For The Comparison Of Timing Behavior Applied To The Pink Salmon Fisheries Of Prince William Sound, Alaska, Louis J. Rugolo

OES Theses and Dissertations

Harvest control in salmonid fisheries was examined as a problem in the formulation of regulations which restrict time and area of fishing. An ability to rigorously define and compare the form of the progression of migration across time and between harvest areas was judged fundamental to objective harvest decisions. Identification and evaluation of statistical methods appropriate to the comparison of empirical migratory time densities was performed.

The development of the measure of central tendency (mean date) of the time density as the consistent, unbiased estimator of migratory behavior was given. Practical evidence demonstrated that the mean date was highly resistant ...


Liver Lesions In Winter Flounder (Pseudopleuronectes Americanus) From Jamaica Bay, New York: Indications Of Environmental Degradation, John T. Tanacredi Ph.D., Thomas P. Augspurger, Roger L. Herman, Jeff S. Hatfield Mar 1994

Liver Lesions In Winter Flounder (Pseudopleuronectes Americanus) From Jamaica Bay, New York: Indications Of Environmental Degradation, John T. Tanacredi Ph.D., Thomas P. Augspurger, Roger L. Herman, Jeff S. Hatfield

Faculty Works: CERCOM

Liver sections of winter flounder (Pseudopleuronectes americanus) collected from Jamaica Bay and Shinnecock Bay, New York, in 1989, were examined microscopically to determine the pervasiveness of liver lesions observed previously in Jamaica Bay winter flounder. Neoplastic lesions were not detected in fish from Jamaica Bay or the Shinnecock Bay reference site. Twenty-two percent of Jamaica Bay winter flounder examined (n=103) had unusual vacuolization of hepatocytes and biliary pre-ductal and ductal cells (referred to hereafter as the vacuolated cell lesion). The lesion, identical to that found in 25% of Jamaica Bay winter flounder examined in 1988, has previously been identified ...


A Profile Of The Oyster Industry Northeastern United States, Douglas Lipton, James Kirkley Feb 1994

A Profile Of The Oyster Industry Northeastern United States, Douglas Lipton, James Kirkley

Reports

This is a critical period for the future of the east coast oyster industry. This report documents the dramatic decline in industry output which has been the impetus for a publicly funded program to "revtalize" the industry. Oyster biologists argue over the severityy of the decline and the cause, and also the potential remedies. Should non-native oysters, specifically Crassostrea gigas, be introduced into the region to replace the native oyster production? Are there ways to manage around the devastating oyster diseases MSX and Dermo? Will large populations of oysters significantly improve the water quality in currentiy degraded areas?

While these ...


Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation Jan 1994

Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation

Publications (WR)

Cover is an important component of aquatic habitat and fisheries management. Fisheries biologists often try to improve habitats through the addition of natural and artificial material to improve cover diversity and complexity. Habitat-improvement programs range from submerging used Christmas trees to more complex programs using sophisticated artificial habitat modules. Used automobile tires have been employed in the large scale construction of reefs and fish attractors in marine environments and to a lesser extent in freshwater and have been recognized as a durable, inexpensive and long-lasting material which benefits fishery communities.

Recent studies by the U.S. Bureau of Reclamation have ...


Sport Fisheries Of The Belgrade Lakes, Maine Department Of Inland Fisheries & Wildlife Jan 1994

Sport Fisheries Of The Belgrade Lakes, Maine Department Of Inland Fisheries & Wildlife

Maine Collection

Sport Fisheries of the Belgrade Lake

Maine Department of Inland Fisheries & Wildlife, Augusta, Maine 1994.

Contents: Belgrade Lakes Chain, Some Vital Statistics / Some Features of the Seven Major Waters of the Belgrade Chain of Lakes / A Partial List of Fish Species That Occur in the Major Waters of the Belgrade Chain of Lakes / East Pond Oakland and Smithfield / Great Pond Oakland, Belgrade, and Rome / Long Pond Mt. Vernon, Rome, and Belgrade / Messalonskee Lake Oakland and Belgrade / North Pond Smithfield, Rome, and Mercer / Salmon Lake and McGrath Pond Belgrade and Oakland



Invasion Of An Exotic Species : Stop The Zebra Mussel! Activities And Resources For Grades 8-12., Vicki P. Clark, Thomas J. Millar Jan 1994

Invasion Of An Exotic Species : Stop The Zebra Mussel! Activities And Resources For Grades 8-12., Vicki P. Clark, Thomas J. Millar

Reports

No abstract provided.


Summer Habitat Use Of Littoral-Zone Fishes In Lake Tahoe And The Effects Of Shoreline Structures, D. Beauchamp, E. Byron, Wayne A. Wurtsbaugh Jan 1994

Summer Habitat Use Of Littoral-Zone Fishes In Lake Tahoe And The Effects Of Shoreline Structures, D. Beauchamp, E. Byron, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

We used scuba observations to determine summer habitat use and the effects of piers on the littoral-zone fish community in Lake Tahoe, California–Nevada. Habitat complexity declined with depth. Over 50% of the littoral zone less than 2 m deep was composed of complex boulder substrates, but this substrate represented less than 10% of the habitat between 10 and 18 m deep. A severe drought lowered the surface elevation of the lake 2 m and reduced the wetted complex rocky habitat by 20% between the 0- and l0-m isobaths (referenced to the mean lake level of 1,899 m above ...


A Trophic Gradient Analysis Of Lake Powell: The 1994 Utah State University Aquatic Ecology Laboratory Analyses, Wayne Wurtsbaugh, Megan Barker, Ron Brunson, David Fogle, Scott Hawxhurst, Chad Mellison, Lis Phillips, Felipe Queiroz, Daniel Zamecnik Jan 1994

A Trophic Gradient Analysis Of Lake Powell: The 1994 Utah State University Aquatic Ecology Laboratory Analyses, Wayne Wurtsbaugh, Megan Barker, Ron Brunson, David Fogle, Scott Hawxhurst, Chad Mellison, Lis Phillips, Felipe Queiroz, Daniel Zamecnik

Watershed Sciences Faculty Publications

From 9-11 April, 1994, the Aquatic Ecology Laboratory Class (FW462) of Utah State University sampled the upper reaches of Lake Powell to assess if a trophic gradient existed. We °ampled physical and chemical parameters (temperature, oxygen, conductivity, and total phosphorus), phytoplankton chlorophyll a, littoral and pelagic zooplankton biomass and composition, littoral and profundal benthic invertebrates, and fish abundance measured in the littoral zone (gill nets) and the pelagic zone (hydroacoustics). Data was collected along the upper 50 miles of the reservoir between Bullfrog and the Hite marina near the Colorado River inflow.

Our field trip was done just prior to ...


Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1993-1994 Annual Report, 1 September 1993 - 31 August 1994, Bruce W. Hill, Joseph G. Loesch Jan 1994

Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1993-1994 Annual Report, 1 September 1993 - 31 August 1994, Bruce W. Hill, Joseph G. Loesch

Reports

No abstract provided.


Habitat Selection By Lacustrine Rainbow Trout Within Gradients Of Temperature, Oxygen, And Food Availability, Chris Luecke, D. Teuscher Jan 1994

Habitat Selection By Lacustrine Rainbow Trout Within Gradients Of Temperature, Oxygen, And Food Availability, Chris Luecke, D. Teuscher

Watershed Sciences Faculty Publications

Rainbow trout (Oncorhynchus mykiss [Walbaum]) in Castle Lake, California were concentrated at certain depths during day and evening hours. A fish bioenergetics simulation model based on vertical gradients of temperature, oxygen concentration, and food availability indicated that rainbow trout selected habitats that maximized growth rate. In 1 of the 2 years of study, a strong pattern of diel vertical migration of rainbow trout was evident and was associated with vertical migrations of daphnids in the lake. The simulation model correctly predicted the occurrence and magnitude of fish migration. During the day some trout resided at depths with little potential for ...


Potential Range Of The Zebra Mussel, Dreissena Polymorpha, In And Near Virginia, Patrick Baker, Shirley Baker, Roger L. Mann Jan 1994

Potential Range Of The Zebra Mussel, Dreissena Polymorpha, In And Near Virginia, Patrick Baker, Shirley Baker, Roger L. Mann

Reports

This publication is devoted to predictions of the probability of invasion by the zebra mussel, Dreissena polymorpha (and the quagga mussel, Dreissena sp.) to specific bodies of water in Virginia. Probability of invasion is divided into risk and susceptibility. Risk refers to the chance, relative to other sites, that a body of water will be inoculated with Dreissena, in sufficient number to establish a population. Inoculation can occur by natural dispersal, but in the mid-Atlantic region is most likely to-occur though accidental introduction by humans, especially via boat traffic. Susceptibility of a body of water refers to the probability, based ...


Modeling Oyster Populations. Iv. Rates Of Mortality, Population Crashes, And Management, E. N. Powell, J. M. Klinck, E. E. Hofmann, S. M. Ray Jan 1994

Modeling Oyster Populations. Iv. Rates Of Mortality, Population Crashes, And Management, E. N. Powell, J. M. Klinck, E. E. Hofmann, S. M. Ray

CCPO Publications

A time-dependent energy-flow model was used to examine how mortality affects oyster populations over the latitudinal gradient from Galveston Bay, Texas, to Chesapeake Bay, Virginia. Simulations using different mortality rates showed that mortality is required for market-site oysters to be a component of the population's size-frequency distribution; otherwise a population of stunted individuals results. As mortality extends into the juvenile sizes, the population's size frequency shifts toward the larger sizes. In many cases adults increase despite a decrease in overall population abundance. Simulations, in which the timing of mortality varied, showed that oyster populations are more susceptible to ...


Modeling Oyster Populations Ii. Adult Size And Reproductive Effort, E. E. Hofmann, J. M. Klinck, E. N. Powell, S. Boyles, M. Ellis Jan 1994

Modeling Oyster Populations Ii. Adult Size And Reproductive Effort, E. E. Hofmann, J. M. Klinck, E. N. Powell, S. Boyles, M. Ellis

CCPO Publications

A time-dependent model of energy flow in post-settlement oyster populations is used to examine the factors that influence adult size and reproductive effort in a particular habitat, Galveston Bay, Texas, and in habitats that extend from Laguna Madre, Texas to Chesapeake Bay. The simulated populations show that adult size and reproductive effort are determined by the allocation of net production to somatic or reproductive tissue development and the rate of food acquisition, both of which are temperature dependent. For similar food conditions, increased temperature reduces the allocation of net production to somatic tissue and increases the rate of food acquisition ...