Life Sciences Commons^™

Increased Feeding And Nutrient Excretion Of Adult Antarctic Krill, Euphausia Superba, Exposed To Enhanced Carbon Dioxide (Co2), Gk Saba, O Schofield, Jj Torres, Eh Ombres, Deborah K. Steinberg

VIMS Articles

Ocean acidification has a wide-ranging potential for impacting the physiology and metabolism of zooplankton. Sufficiently elevated CO2 concentrations can alter internal acid-base balance, compromising homeostatic regulation and disrupting internal systems ranging from oxygen transport to ion balance. We assessed feeding and nutrient excretion rates in natural populations of the keystone species Euphausia superba (Antarctic krill) by conducting a CO2 perturbation experiment at ambient and elevated atmospheric CO2 levels in January 2011 along the West Antarctic Peninsula (WAP). Under elevated CO2 conditions (similar to 672 ppm), ingestion rates of krill averaged 78 mu g C individual(-1) d(-1) and were 3.5 times …

Modeling Of Oyster Larval Connectivity For Cbf In Support Of Noaa’S Community-Based Restoration Program & Restore America’S Estuaries Oyster And Reef Balls On Sanctuary Reefs In Md And Va - Phase Three, Mac Sisson, Jian Shen

Reports

1. The overarching goal of the Chesapeake Bay Foundation (CBF) for this project has been to enhance the Chesapeake Bay’s oyster population. In Virginia, CBF is working with partners to focus restoration efforts on the Lafayette River in order to bring the river’s biomass and reef substrate to a threshold level that will show a systemic response in terms of enhanced spatset. Portions of their grant have funded the hydrodynamic modeling of the Lafayette River recently performed and herein reported. 2. VIMS personnel have modified its existing three-dimensional hydrodynamic model of the Lafayette/Elizabeth/James Rivers to conduct larval connectivity simulations. The …

Assessment Of The Economic Impacts Of Recreational Boating In Virginia, Thomas J. Murray

Reports

Virginia is home to more than 200,000 recreational boats, providing a gateway to marine recreation in Chesapeake Bay and offshore waters. Virginia’s importance to boating access carries with it an expanding economy related to boating and boating related industries.

In addition to the large group of boater-citizens who reside in Virginia, local marine businesses such as marinas also provide access and berthing to many non-locally owned watercraft. While watercraft registrations provide a partial and useful estimate of the stock of boats in a region, the true economic impact arising from recreational boating primarily depends upon the type of boats as …

Reducing Yellowtail Flounder Bycatch In The Sea Scallop Dredge Fishery: Twine Top Modifications, Kelli Milleville Wright, David Rudders, William D. Dupaul

Reports

No abstract provided.

Harmful Algal Bloom (Hab) Primer For The Virginia Shellfish Industry, Kimberly S. Reece, Karen Hudson

Reports

No abstract provided.

Blue Crab Industry - Oyster Aquaculture Training And Transition June 2011- June 2012 Final Report, Matthew Richmond

Reports

No abstract provided.

Selective Feeding On Nutrient-Rich Particles By Gizzard Shad Dorosoma Cepedianum Does Not Involve Mechanical Sorting, M. K. Heidman, L. L. Holley, Randolph Chambers, S. Laurie Sanderson

Arts & Sciences Articles

Previous field and laboratory studies have concluded that suspension-feeding detritivorous fish such as gizzard shad Dorosoma cepedianum selectively ingest nutrient-rich particles using either mechanical sorting within the oropharyngeal cavity or behavioral selectivity within the environment, but none have distinguished between these hypothesized selection mechanisms. To determine whether mechanical selectivity occurs within the oropharyngeal cavity, gizzard shad were fed particles of standardized size but different carbon and nitrogen content in homogeneous particle suspensions vs. non-homogeneous particle distributions. By comparing foregut and epibranchial organ contents with the particles available in a homogeneous suspension, we demonstrated that the fish did not use mechanical …

2012 Cultchless (Single Seed) Oyster Crop Budgets For Virginia User Manual, Karen Hudson, Dan Kauffman, Thomas J. Murray, Alexander Solomon

Reports

No abstract provided.

A Pilot Project For Assessing The Socioeconomic Issues Facing Maryland’S Working Waterfront; An Inventory Of The Choptank River Watershed, Thomas J. Murray

Reports

No abstract provided.

Simulated Performance Of Catch Curve Methods For Estimating Total Mortality Rate, Matthew W. Smith, John M. Hoenig

Reports

This document has been issued as VIMS Data Report 60 and provides additional simulation results for Smith et al. (2012) published in the North American Journal of Fisheries Management. Catch curve methods are a basic tool of population dynamics for estimating total mortality rate from age composition. There are a number of methodological issues which remain unresolved. Smith et al. (2012) attempts to provide guidelines on the use of these methods based on extensive Monte Carlo simulations. This report presents additional simulation results to supplement the results in the journal article. The estimators, evaluation criteria, simulation procedures, and conditions simulated …

Anthropogenic Noise Is Associated With Reductions In The Productivity Of Breeding Eastern Bluebirds (Sialia Sialis), Caitlin R. Kight, Margaret S. Saha, John P. Swaddle

Arts & Sciences Articles

Although previous studies have related variations in environmental noise levels with alterations in communication behaviors of birds, little work has investigated the potential long-term implications of living or breeding in noisy habitats. However, noise has the potential to reduce fitness, both directly (because it is a physiological stressor) and indirectly (by masking important vocalizations and/or leading to behavioral changes). Here, we quantified acoustic conditions in active breeding territories of male Eastern Bluebirds (Sialia sialis). Simultaneously, we measured four fitness indicators: cuckoldry rates, brood growth rate and condition, and number of fledglings produced (i.e., productivity). Increases in environmental noise …

Evaluating Recruitment Of American Eel, Anguilla Rostrata, In The Potomac River (Spring 2012), Troy D. Tuckey, Mary C. Fabrizio

Reports

The Atlantic States Marine Fisheries Commission (ASMFC) adopted the Interstate Fishery Management Plan (FMP) for the American eel in November 1999. The FMP focuses on increasing coastal states’ efforts to collect American eel data through both fishery-dependent and fishery-independent studies. Consequently, member jurisdictions agreed to implement an annual survey for young-of-year (YOY) American eels. The survey is intended to “…characterize trends in annual recruitment of the YOY eels over time [to produce a] qualitative appraisal of the annual recruitment of American eel to the U.S. Atlantic Coast” (ASMFC 2000). The development of these surveys began in 2000 with full implementation …

Multiple Novel Signals Mediate Thyroid Hormone Receptor Nuclear Import And Export, Manohara S. Mavinakere, Jeremy M. Powers, Kelly S. Subramanian, Vincent R. Roggero, Lizabeth A. Allison

Arts & Sciences Articles

Thyroid hormone receptor (TR) is a member of the nuclear receptor superfamily that shuttles between the cytosol and nucleus. The fine balance between nuclear import and export of TR has emerged as a critical control point for modulating thyroid hormone-responsive gene expression; however, sequence motifs of TR that mediate shuttling are not fully defined. Here, we characterized multiple signals that direct TR shuttling. Along with the known nuclear localization signal in the hinge domain, we identified a novel nuclear localization signal in the A/B domain of thyroid hormone receptor a1 that is absent in thyroid hormone receptor B1 and inactive …

An Assessment Of Sea Scallop Abundance And Distribution In Selected Areas: Nantucket Lightship Closed Area, Hudson Canyon Closed Area, And The Delmarva Closed Area, David Rudders, William D. Dupaul, Jessica Bergeron

Reports

No abstract provided.

The Role Of Mycobacteriosis In Elevated Natural Mortality Of Chesapeake Bay Striped Bass: Developing Better Models For Stock Assessment And Management : A Final Report, Wolfgang K. Vogelbein, John Hoenig, David Gauthier, Matthew Smith, Phil Sadler, Howard Kator, Martha Rhodes

Reports

Mycobacteriosis is a chronic systemic disease of fishes caused by bacteria belonging to the genus Mycobacterium. The disease currently affects striped bass throughout Chesapeake Bay and prevalence is higher than 90% in certain age groups. Two recently described species, M. shottsii and M. pseudoshottsii, are the most common isolates obtained from diseased fish and are considered the primary etiologic agents. Recent indications that natural mortality (M) has become elevated in Chesapeake Bay striped bass and that mycobacteriosis may be the underlying cause, has caused concern among fishermen, fisheries managers and scientists. However, fundamental questions, such as transmission mode, duration of …

Final Report: An Assessment Of Sea Scallop Abundance And Distribution In A Selected Closed Area: Georges Bank Closed Area Ii, David Rudders, William D. Dupaul

Reports

No abstract provided.

Final Report : An Assessment Of Sea Scallop Abundance And Distribution In Open Access Areas: New York Bight And The Southern New England Area, David Rudders, William D. Dupaul

Reports

No abstract provided.

An Assessment Of Sea Scallop Abundance And Distribution In A Selected Closed Area: Delmarva Closed Area, David Rudders, William D. Dupaul

Reports

No abstract provided.

Marine Resource Bulletin Vol. 44, No. 2, Virginia Sea Grant, Virginia Institute Of Marine Science

Virginia Marine Resource Bulletin

In This Issue

Research Ready 2

Virginia Sea Grant supports a portfolio of science and social science research that has tangible benefits for coastal ecosystems and communities. Some of these exciting research efforts are featured in this issue.

Terrapin Files 4

Diamondback terrapins face a variety of threats—from coastal development to crab fishing. A team of VASG-funded researchers are mapping terrapin habitat and threats to aid in the development of effective management strategies.

Nutrient Flow in Clam Aquaculture 8

Virginia’s Eastern Shore is home to a fast-growing clam aquaculture in - dustry. This photo-essay features research on the effects of …

Circle Hooks In Commercial, Recreational, And Artisanal Fisheries: Research Status And Needs For Improved Conservation And Management, Je Serafy, Sj Cooke, Ga Diaz, John Graves, Et Al

VIMS Articles

The intent of convening the International Symposium on Circle Hooks in Research, Management, and Conservation was to yield a contemporary, science-based assessment of the management and conservation utility of circle hooks in commercial, recreational, and artisanal fisheries around the globe. The symposium objective was to provide a forum for individuals, organizations, and agencies to share relevant research results and perspectives. Based on the presentations, an examination of the literature, and the collective experience and knowledge of the authors, we provide a brief overview of the current status of circle hook research along with a list of research needs, with a …

Incorporating Circle Hooks Into Atlantic Pelagic Fisheries: Case Studies From The Commercial Tuna/Swordfish Longline And Recreational Billfish Fisheries, John Graves, Az Horodysky, Dw Kerstetter

VIMS Articles

An emerging body of literature has demonstrated the benefits of the use of circle hooks relative to standard J-hooks in commercial and recreational fisheries. In the pelagic longline fishery for tunas (Thunnus spp.) and swordfish (Xiphias gladius Linnaeus, 1758), the use of circle hooks has resulted in greater catch rates of some target species, lower catch rates of some bycatch species, and a higher percentage of many target and bycatch species alive at the time of haulback (gear retrieval). However, a lack of agreement among results of studies conducted in different fisheries and areas, using different baits and rigging techniques, …

Constraints On Acoustic Signaling Among Birds Breeding In Secondary Cavities: The Effects Of Weather, Cavity Material, And Noise On Sound Propagation, John P. Swaddle, Caitlin R. Kight, Saji Perera, Eduardo Davila-Reyes, Shena Sikora

Arts & Sciences Articles

Increasing evidence suggests that anthropogenic noise from urbanization affects animal acoustic communication. We investigated whether the begging calls of nestling Eastern Bluebirds (Sialia sialis) varied along a disturbance gradient of ambient noise. Contrary to our prediction and the results of a previous study of nestling Tree Swallows (Tachycineta bicolor), we found that nestling Eastern Bluebirds did not increase the amplitude or structural characteristics—including frequency, rate, and duration—of their vocalizations in response to ambient noise. However, we found that prevalent temperature and humidity conditions attenuated begging calls. Specifically, in warmer, more humid weather, vocalizations of nestling Eastern …

2012 Annual Report Estimating Relative Juvenile Abundance Of Ecologically Important Finfish In The Virginia Portion Of Chesapeake Bay, Troy D. Tuckey, Mary C. Fabrizio

Reports

No abstract provided.

Acoustic Space Is Affected By Anthropogenic Habitat Features: Implications For Avian Vocal Communication, Caitlin R. Kight, Mark H. Hinders, John P. Swaddle

Arts & Sciences Articles

Human-altered landscapes often include structural features, such as higher levels of impervious surface cover (ISC) and less vegetation, that are likely to affect the transmission of avian vocalizations. We investigated the relationships between human habitat modifications and signal transmission by measuring four acoustic parameters—persistence, reverberation, and signal-to-noise ratio (SNR) of broadcast tones, as well as absolute ambient noise level—in each of 39 avian breeding territories across an anthropogenic disturbance gradient. Using a geographic information system, we quantified the amounts of different habitat features (e.g., ISC, grass, trees) at each site; a principal component analysis was used to identify which of …

Virginia Shellfish Aquaculture Situation And Outlook Report : Results Of The 2011 Virginia Shellfish Aquaculture Crop Reporting Survey, Thomas J. Murray, Karen Hudson

Reports

The shellfish aquaculture industry in Virginia continues to grow, adding significant value to the state’s seafood marketplace. Today, watermen continue to harvest both hard clams and oysters from the state’s public resources, albeit at diminished rates. At the same time, Virginia’s watermen-farmers are providing growing quantities of additional quality shellfish to consumers. In recent years, folliowing the lead of the hard clam industry, a significant transition to intensive aquaculture of native oysters is underway. The once-extensive oyster planting utilizing wild seed has contracted primarily as a result of endemic oyster diseases and increasing wildlife predation of seed oysters. In its …

Cumulative Lesioning Of Respiratory Interneurons Disrupts And Precludes Motor Rhythms In Vitro, Xueying Wang, John A. Hayes, Christopher A. Del Negro

Arts & Sciences Articles

How brain functions degenerate in the face of progressive cell loss is an important issue that pertains to neurodegenerative diseases and basic properties of neural networks. We developed an automated system that uses two-photon microscopy to detect rhythmic neurons from calcium activity, and then individually laser ablates the targets while monitoring network function in real time. We applied this system to the mammalian respiratory oscillator located in the pre-Bötzinger Complex (preBötC) of the ventral medulla, which spontaneously generates breathing-related motor activity in vitro. Here, we show that cumulatively deleting preBötC neurons progressively decreases respiratory frequency and the amplitude of motor …

Annual Report - 2011 Data Collection And Analysis In Support Of Single And Multispecies Stock Assessments In Chesapeake Bay: The Chesapeake Bay Multispecies Monitoring And Assessment Program, Christopher F. Bonzek, James Gartland, Debra J. Gauthier, Robert J. Latour

Reports

Historically, fisheries management has been based on the results of single-species stock assessment models that focus on the interplay between exploitation level and sustainability. There currently exists a suite of standard and accepted analytical frameworks (e.g., virtual population analysis (VPA), biomass dynamic production modeling, delay difference models, etc.) for assessing the stocks, projecting future stock size, evaluating recovery schedules and rebuilding strategies for overfished stocks, setting allowable catches, and estimating fishing mortality or exploitation rates. A variety of methods also exist to integrate the biological system and the fisheries resource system, thereby enabling the evaluation of alternative management strategies on …

Virginia Game Fish Tagging Program Annual Report 2011, Susanna Musick, Lewis Gillingham

Reports

Through 2011, the Virginia Game Fish Tagging Program has maintained a 17-year database of records for tagged and recaptured fish. The program is a co-operative project of the Virginia Saltwater Fishing Tournament (under the Virginia Marine Resources Commission-VMRC) and the Virginia Institute of Marine Science (VIMS) of the College of William and Mary (under the VIMS Marine Advisory Program).

Global Patterns In The Impact Of Marine Herbivores On Benthic Primary Producers, Alistair G.B. Poore, Alexandra H. Campbell, Ross Coleman, Graham J. Edgar, Veijo Jormalainen, Pamela L. Reynolds, Erik E. Sotka, John J. Stachowicz, Richard Taylor, Mathew A. Vanderklift, J. Emmett Duffy

VIMS Articles

Despite the importance of consumers in structuring communities, and the widespread assumption that consumption is strongest at low latitudes, empirical tests for global scale patterns in the magnitude of consumer impacts are limited. In marine systems, the long tradition of experimentally excluding herbivores in their natural environments allows consumer impacts to be quantified on global scales using consistent methodology. We present a quantitative synthesis of 613 marine herbivore exclusion experiments to test the influence of consumer traits, producer traits and the environment on the strength of herbivore impacts on benthic producers. Across the globe, marine herbivores profoundly reduced producer abundance …

Effects Of Trophic Skewing Of Species Richness Onecosystem Functioning In A Diverse Marine Community, Pamela L. Reynolds, John F. Bruno

VIMS Articles

Widespread overharvesting of top consumers of the world's ecosystems has "skewed" food webs, in terms of biomass and species richness, towards a generally greater domination at lower trophic levels. This skewing is exacerbated in locations where exotic species are predominantly low-trophic level consumers such as benthic macrophytes, detritivores, and filter feeders. However, in some systems where numerous exotic predators have been added, sometimes purposefully as in many freshwater systems, food webs are skewed in the opposite direction toward consumer dominance. Little is known about how such modifications to food web topology, e.g., changes in the ratio of predator to prey …