Life Sciences Commons^™

Collaborative Research: Life Histories Of Species In The Genus Calanus In The North Atlantic And North Pacific Oceans And Responses To Climate Forcing, Jeffrey Runge, Andrew J. Pershing

University of Maine Office of Research Administration: Grant Reports

Species in the genus Calanus are predominant in the mesozooplankton of the North Atlantic and North Pacific Oceans. Their key role in marine food web interactions has been recognized in GLOBEC programs, both in the U.S. and internationally. Considerable knowledge of life history characteristics, including growth, reproduction, mortality, diapause behavior and demography has been acquired from both laboratory experiments and measurements at sea. This project reviews and synthesizes this knowledge and uses it to develop an Individual Based Life Cycle model for sibling species in two sympatric species pairs, C.marshallae and C. pacificus in the North Pacific Ocean and C. …

Population Dynamics Of The Sub-Arctic Copepod Calanus Finmarchicus In The Gulf Of Maine: Demography And Mortality Estimation, Cameron R. S. Thompson

Electronic Theses and Dissertations

Calanus finmarchicus is a widely distributed copepod species that dominants the zooplankton community in the Gulf of Maine. It is of particular interest in its role as a major food source for the endangered northern right whale and stocks of herring, mackerel and cod. More accurate coupled models to predict its distribution requires better life history models. However, due to the difficulty in estimating it, mortality is often used as a closure term in those models; the value is justified mathematically rather than ecologically. Instantaneous mortality is difficult to measure, but the Vertical Life Table method (VLT) has gained some …

Analysis Of Extracellular Proteins Expressed By Host, Crassostrea Virginica And Pathogen, Roseovarius Crassostreae In Roseovarius Oyster Disease, Erin Macro

Electronic Theses and Dissertations

Roseovarius Oyster Disease (ROD) involves the colonization of the inner shell of the Eastern Oyster (Crassostrea virginica) by the marine alpha-proteobacterium Roseovarius crassostreae. The ensuing disease can result in upwards of 90% mortality in hatchery-raised juvenile (< 25 mm shell length) oysters. Symptoms of ROD include heavy, brown ring deposits of conchiolin on the surface of the shell, as well as uneven valve growth and shell curvature. Although the bacterium does not invade oyster tissue or digestive tract, fluorescent localization of an R. crassostreae biofilm on the inner shells of ROD-affected oysters, and toxic effects of R. crassotreae extracellular products on hemocytes and larval oysters suggest that a chemical warfare takes place between the R. crassostreae biofilm and the oyster host. In this thesis, I cultured R. crassostreae under laboratory conditions and analyzed the affects of physical growth condition, temperature, culture volume, and iron limitation on bacterial growth and bacterial extracellular protein (ECP) production. Culture growth rate increased with increasing temperature. Iron limitation resulted in slower growth but had no affect on maximum culture density. Iron limited cells produced a greater volume of ECPs, especially at low cell density. ECPs from liquid and solid-phase cultures were analyzed by LC-tandem mass spectrometry. The resulting protein sequences had high similarity to proteins in other bacterial species that act as virulence factors in other hosts, including metal transporters (2), proteases (2) and a surface-associated GroEL chaperonin. I also exposed live oysters to ECPs of live R. crassostreae cells by embedding a filter capsule into the oyster shell. I sampled extrapallial fluid from oysters pre-exposure and post-exposure and analyzed the relative expression of the oyster defense protein dominin in addition to the extent of brown shell deposition as a function of bacterial presence. The injury response due to capsule embedment masked any potential response by oysters to R. crassostreae ECPs.

The Lobster Bulletin, Fall 2012, Lobster Institute, University Of Maine

Lobster Bulletin

The Lobster Bulletin newsletter includes research updates, and information on lobsters and the lobster industry. The Lobster Institute at the University of Maine is dedicated to protecting and conserving the lobster resource, and enhancing lobstering as an industry and a way of life.

Headlines in the Fall 2012 issue include:

• Group Seeks to Protect Ocean by Promoting Better Lawn Care Practices
• Lobster Institute 25th Anniversary Celebration Continues
• Maine Conforms First-Ever Case of West Nile Virus
• Research Report: Direct Determination of Age in Lobsters
• Research Report: Lobster Cam Back Online Soon
• Lobster Council Taking Giant Step Forward

The Lobster Bulletin, Summer 2012, Lobster Institute, University Of Maine

Lobster Bulletin

The Lobster Bulletin newsletter includes research updates, and information on lobsters and the lobster industry. The Lobster Institute at the University of Maine is dedicated to protecting and conserving the lobster resource, and enhancing lobstering as an industry and a way of life.

Headlines in the Summer 2012 issue include:

• Understanding the Soft Shell Lobster
• Lobster Institute to Host UMaine Lobster Showcase to Celebrate Its 25th Anniversary
• New Lobster Mandatory V-Notch Rules In New York Marine Waters
• Research Report: Effects of Acidification on Juvenile Lobsters Being Studied at UMaine
• Research Report: Fact Sheet Released on Status of Eutrophication in the …

Salinity Tolerance Of The Oyster Mudworm Polydora Websteri, Shannon W. Brown

Honors College

The marine worm Polydora websteri is one of many polychaete species that burrow into the shells of commercially important shellfish. In Maine, local eastern oyster (Crassostrea virginica) farmers are struggling with an infestation of this pest. The worm egests muddy wastes in its burrow causing irritation to the oyster. In response, the oyster secretes new shell material over the burrow forming mud blisters. These blisters are unsightly and decrease the market value of infested oysters, especially for oysters sold in the half-shell trade. In addition to the reduction in market value, the worm may cause physiological stress on …

Environmental Factors Linked To Harmful Algal Bloom Induced Shellfish Toxicity In Cobscook Bay, Maine, Hannah M. Horecka

Honors College

The Gulf of Maine experiences annual closures of shellfish harvesting due to the accumulation of toxins resulting from harmful algal blooms of the dinoflagellate Alexandrium spp. If ingested by humans, these toxins can cause paralytic shellfish poisoning. The factors affecting the timing, location, and magnitude of these events remain poorly understood. Previous work found no obvious correlations between Gulf of Maine oceanographic variability and interannual variability in toxicity in the strongly tidally mixed eastern Maine coastal region in the vicinity of Cobscook Bay. Using 21 years (1985-2005) of Maine Department of Marine Resources shellfish toxicity data, interannual variability in …

The Lobster Bulletin, Spring 2012, Lobster Institute, University Of Maine

Lobster Bulletin

The Lobster Bulletin newsletter includes research updates, and information on lobsters and the lobster industry. The Lobster Institute at the University of Maine is dedicated to protecting and conserving the lobster resource, and enhancing lobstering as an industry and a way of life.

Headlines in the Spring 2012 issue include:

• Lobster Institute’s 2012 Canadian/U.S. Lobstermen’s Town Meeting Attracts over 100
• Darden Restaurants to Establish a “Lobster Farm” in Malaysia
• National Seafood Marketing Coalition Addresses U.S. Senate
• Lobster Science Symposium Planned for November
• Research Report: Warm Water Affecting Lobsters
• Research Report: Steneck participates in Task Force on Global Fishing
• Lobster Institute’s …

Improvements To Sampling From The Research Vessel Ira C, Mary Jane Perry

University of Maine Office of Research Administration: Grant Reports

The University of Maine's Darling Marine Center is awarded a grant to equip the 42-ft Ira C., the Center's largest vessel, with a well instrumented CTD, including optical sensors and a small array of sampling bottles plus a winch with conducting cable so that CTD work from the Ira C. no longer needs to depend on users bringing their own CTD and lowering by hand. This proposal is to expand the environments and variables within effective reach of the University of Maine's marine laboratory, the Ira C. Darling Marine Center (the Center) in midcoast Maine. The Center is within a …