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Environmental Change In The Coastal Environment: Challenges For The Selection And Propagation Of Filter Feeding Species In Aquaculture, Stock Enhancement And Environmental Rehabilitation, Roger L. Mann
VIMS Articles
Selection of species for aquaculture, fishery stock enhancement and environmental rehabilitation or restoration in the coastal zone requires consideration of the fact that species have evolved over geological time whereas changes in the coastal environment have occurred predominantly over recent historical time, often with the largest changes occurring within the past decades of human activity. The evolutionary issue is particularly noted with filter feeding molluscs, where extant species supporting both major natural fisheries and aquaculture have ancient lineages and evolved in environments that may have differed considerably from the locally turbid, nutrient enriched, disturbed (through watershed change and local activity) …
Decadal Scale Changes In Seasonal Patterns Of Oyster Recruitment In The Virginia Sub Estuaries Of The Chesapeake Bay, Melissa Southworth, Roger L. Mann
Decadal Scale Changes In Seasonal Patterns Of Oyster Recruitment In The Virginia Sub Estuaries Of The Chesapeake Bay, Melissa Southworth, Roger L. Mann
VIMS Articles
Reproductive periodicity of sessile estuarine invertebrates reflects local seasonality of environmental (temperature, salinity) and biologic (food) parameters. Estuaries are ephemeral features in geologic time but considered somewhat constant in the course of recent human history (decadal time scales). Analyses of long-term trends in eastern oyster (Crassostrea virginica) settlement periodicity since 1960 in three major Chesapeake Bay rivers (James, Piankatank and Great Wicomico Rivers) of the Chesapeake Bay show marked changes within the 4-decade time frame. The 50th percentile of cumulative recruitment occurs between day 194 and 250 of the year depending on year and location. Significant coherence in interannual variation …
Evidence Of Shark Predation And Scavenging On Fishes Equipped With Pop-Up Satellite Archival Tags, David Kerstetter, Jeffery J. Polovina, John Graves
Evidence Of Shark Predation And Scavenging On Fishes Equipped With Pop-Up Satellite Archival Tags, David Kerstetter, Jeffery J. Polovina, John Graves
VIMS Articles
No abstract provided.
Site Selection For Oyster Habitat Rehabilitation In The Virginia Portion Of The Chesapeake Bay: A Commentary, Roger L. Mann, Da Evans
Site Selection For Oyster Habitat Rehabilitation In The Virginia Portion Of The Chesapeake Bay: A Commentary, Roger L. Mann, Da Evans
VIMS Articles
A significant body of knowledge has been generated during the past decade on disease tolerance of the native oyster Crassostrea virginica. A major opportunity to move into a large-scale field application phase of that knowledge has been presented by a 10-y commitment by the U.S. Army Corps of Engineers (ACOE) to a partnership in Virginia focused on widespread restoration of oyster resources for ecological purposes. The partnership involves ACOE, the Virginia Institute of Marine Science (VIMS), the Virginia Marine Resources Commission (VMRC), and the Chesapeake Bay Foundation (CBF). This collaboration will effect a sequenced restoration effort involving site selection, site …
Deterministic And Stochastic Capacity Estimation For Fishery Capacity Reduction, James Kirkley, Catherine Morrison Paul, Dales Squires
Deterministic And Stochastic Capacity Estimation For Fishery Capacity Reduction, James Kirkley, Catherine Morrison Paul, Dales Squires
VIMS Articles
Deterministic data envelopment analysis (DEA) and stochastic pro- duction frontier (SPF) models are alternative methods for estimating capacity in fisheries. Fishery managers should be aware of likely differences in the capacity estimates obtained from these approaches if such estimates are to be used to support capacity reduction programs. In this paper, we provide a comparative analysis of DEA and SPF capacity estimates for a variety of possible capacity concepts using a panel data set for 10 vessels in the U.S. Northwest Atlantic scallop fishery. We find that DEA capacity output measures are higher than cor- responding SPF measures, but that …
Short-Run Welfare Losses From Essential Fish Habitat Designations For The Surfclam And Ocean Quahog Fisheries, Robert L. Hicks, James Kirkley, Iver E. Strand Jr.
Short-Run Welfare Losses From Essential Fish Habitat Designations For The Surfclam And Ocean Quahog Fisheries, Robert L. Hicks, James Kirkley, Iver E. Strand Jr.
VIMS Articles
In this paper, we present a spatial model of fishing that can be used to assess some of the economic welfare losses to producers from setting aside essential fish habitat (EFH) areas. The paper demonstrates how spatially explicit behavioral models of fishing are estimated, how these models can be used to measure welfare losses to fishermen, and how these models can then, in turn, be used to simulate fishing behavior. In developing the spatial model of fishing behavior, the work incorporates ideas of congestion and information effects, and we show a modification of standard welfare measures that accounts for these …
A Comparison Of Dredge And Patent Tongs For Estimation Of Oyster Populations, Roger L. Mann, Melissa Southworth, Jm Harding, J Wesson
A Comparison Of Dredge And Patent Tongs For Estimation Of Oyster Populations, Roger L. Mann, Melissa Southworth, Jm Harding, J Wesson
VIMS Articles
Exploited oyster stocks on public grounds in Virginia waters are subject to regular surveys effected using a traditional oyster dredge and, more recently, patent tongs. Dredges provide semiquantitative data, have been used with consistency over extended periods (decades), and provide data on population trends. Surveys with patent tongs provide absolute quantification (number of individuals per unit area) of oyster stocks but are more labor intensive. Absolute quantification of dredge data is difficult in that dredges accumulate organisms as they move over the bottom, may not sample with constancy throughout a single dredge haul, and may fill before completion of the …