Data from Virginia-Maryland cooperative fish trawl surveys in Chesapeake Bay - 1957 and 1958 (original) (raw)
BACKGROUND The Chesapeake 2000 (C2K) Agreement commits regional jurisdictions to implement multispecies approaches to fisheries management. The potential for biological interactions and technical interactions within traditional single species management has motivated the development of multispecies approaches. Houde et al. (1998)1 reported the recommendations of a workshop to explore the utility and advisability of adopting multispecies approaches in Chesapeake Bay. An important conclusion of the workshop was the development of coordinated, baywide surveys to estimate key species abundances and to provide biological data on both economically and ecologically important species that are currently lacking (Houde et al. op. cit.). Since 1995, we have conducted research that seeks to provide information that will be needed to design a suitable baywide multispecies survey in support of C2K commitments. This research has several objectives that directly address issues relating to the desig...
2001
Of the 38 federally managed species in the Northeast and Mid-Atlantic regions, 28 have been documented to occur in Chesapeake Bay. Of these 28 species, 21 have been captured by the VIMS Trawl and Seine Surveys since 1988. Catch information for these surveys is examined to determine essential fish habitat for each of these species in the Virginia portion of Chesapeake Bay. For abundant species, both juvenile and adult components of the life history are examined, with less abundant species represented by only total catch. This examination of habitat usage is limited to an analyses of hydrographic parameters such as water temperature, salinity, dissolved oxygen, pH, and depth. In addition to these parameters spatial and temporal components of distribution are presented for each species (and life stage when applicable). Salinity and temperature appear to be the most influential factors in determining distribution of most species. These surveys presented here sample from the Atlantic Ocean to the freshwater portions of several major tributaries nearly 80 miles upstream on a near continuous monthly basis. For most species, there is a clear preference towards waters within a specific salinity range. Since many of these species are migratory and only seasonally present in the Bay, there is also often a strong preference in regards to water temperature as well. To further understand the habitat requirements of these and other Chesapeake Bay species, live bottom types (sponge, sav, hydroids, etc) are being examined (since 1998) in an attempt to find relationships between their densities and fish abundance. ACKNOWLEDGMENTS Thanks is expressed to the many individuals who have participated in field collections over the years, often under difficult and arduous circumstances, especially Captains Deane Estes, Don Seaver, and Paul Gerdes, Hank Brooks, Wendy Lowery, Todd Mathes, and Bob Wood. A special thanks to Hank Brooks for organizing, printing, and copying the final edition and distributing to interested parties.
Chesapeake Bay Trophic Interactions Laboratory Services (CTILS)
2006
Stomach samples or whole fish were obtained from a network of up to eight participating fisheries surveys in the Chesapeake Bay area. Field supplies and sample transport were provided by CTILS. Whole fish were processed for length, weight, and sex determination. Stomachs were removed and analyzed in the laboratory and prey types determined. In support of ecosystem-based fisheries management, estimates of locationspecific diet composition were produced for each species. Comparisons of dietary habits of each species among a range of habitats in the Bay and throughout various time frames were made.
Beach zone fish community structure in the James River, Virginia
1978
A seining survey of the fish fauna of the beach zone in the James River, Virginia, was conducted from July to December 1977. Weekly collections were made at 4 stations resulting in the capture of 17,602 individuals representing 36 species. Abundance and diversity were influenced by large catches of schooling and migratory species utilizing nearshore areas as a nursery ground. Freshwater species diversity peaked in August and September, while mesohaline species diversity peaked in July, September, and November. Cluster analysis was used to define 3 freshwater station groups representing warm, moderate, and cool water temperatures, but was not helpful in analyzing mesohaline stations.
2000
Sheepshead Population Dynamics in Chesapeake Bay, Virginia Recreational catch of sheepshead in Virginia, estimated by MRFSS, has been increasing in recent years. This increase has made local anglers such as the Coastal Conservation Association (CCA) concerned about sheepshead population status as the fishery develops. However, little is known about the Chesapeake Bay sheepshead population beyond minimal catch statistics. Moreover, the population in Chesapeake Bay may be a local stock governed by its unique vital rates. Therefore, specific data on population dynamics of sheepshead stock in Chesapeake Bay must be obtained to provide a scientific base for its management. We are proposing a three-year project to examine age composition, annual growth and mortality rates, and reproductive status of sheepshead in Chesapeake Bay, using this information to establish a baseline for stock assessment of this species in Chesapeake Bay. We present the second year's study here. Fisheries management Population characteristics of sheepshead in Chesapeake Bay will be evaluated and reported to VMRC as basic information for conducting initial stock assessment and for making management policies. The results of this study will indicate the level of fishing that results in a sustainable exploitation of this stock, and whether this stock is separate from those in North Carolina, such that it can be managed independently by Virginia.
Ecological role of blue catfish in Chesapeake Bay communities and implications for management
2011
Rapid increase in abundance and expanded distribution of introduced blue catfi sh Ictalurus furcatus populations in the Chesapeake Bay watershed have raised regional management concerns. This study uses information from multiple surveys to examine expansion of blue catfi sh populations and document their role in tidal river communities. Originally stocked in the James, York, and Rappahannock River systems for development of commercial and recreational fi sheries, blue catfi sh have now been documented in adjacent rivers and have expanded their within-river distribution to oligo-and mesohaline environments. Range expansions coincided with periods of peak abundance in 1996 and 2003 and with the concurrent decline in abundance of native white catfi sh I. catus. Blue catfi sh in these systems use a diverse prey base; various amphipod species typically dominate the diet of smaller individuals (<300 mm fork length [FL]), and fi shes are common prey for larger blue catfi sh (>300 mm FL). Recent studies based on stable isotope analyses suggest that adult blue catfi sh in these systems are apex predators that feed extensively on important fi shery resources, including anadromous shads and herrings Alosa spp. and juvenile Atlantic menhaden Brevoortia tyrannus. Minimizing effects on Chesapeake Bay communities by controlling high densities of blue catfi sh populations is a primary goal of management, but confl icting demands of the commercial and recreational sectors must be resolved. Further, low market demand and human consumption concerns associated with purported accumulation of contaminants in blue catfi sh pose additional complications for regulating these fi sheries.
Patterns and drivers of the demersal fish community of Chesapeake Bay
Marine Ecology Progress Series, 2013
Large-scale research on the environmental, biological, and anthropogenic drivers of fish distributions, abundances, and community structure can identify patterns and trends within systems, provide mechanistic insight into ecosystem functioning, and contribute to ecosystembased fisheries management. This study synthesized 10 yr of extensive fisheries-independent bottom trawl data (2002 to 2011) to evaluate drivers of demersal fish community structure in Chesapeake Bay, the largest estuary in the United States. Changes in community composition were assessed using constrained correspondence analysis. Also, aggregate community metrics (species richness, Simpson diversity, and catch-per-unit-effort [CPUE] of species groups) were modeled using generalized additive models. Five species (Atlantic croaker, white perch, spot, striped bass, and summer flounder) accounted for > 75% of the total trawled biomass. The demersal fish community was primarily structured by the latitudinal salinity gradient that largely differentiated anadromous fishes from coastal shelf spawning species and elasmobranchs, with low overall CPUE and richness in mesohaline waters. Low dissolved oxygen concentrations (below ~4 mg l −1) greatly suppressed CPUE and diversity metrics and appeared to displace fish biomass toward the northern and southern edges of the bay's mainstem channel. Water temperature and month strongly influenced the seasonal dynamics of community composition and metrics. Community composition and biomass shifted after 2007, with a substantial decline in annual CPUE of some species groups. Recruitment and fishing indices for the dominant species were the best predictors of the interannual patterns in community metrics, outperforming various other climatic and biological annual-scale covariates.
Spatial variation in delaware bay (U.S.A.) marsh creek fish assemblages
Estuaries and Coasts, 2001
Delaware Bay is one of the largest estuaries on the U.S. eastern seaboard and is flanked by some of the most extensive salt marshes found in the northeastern U.S. While physicochemical and biotic gradients are known to occur along the long axis of the bay, no studies to date have investigated how the fish assemblage found in salt marsh creeks vary along this axis. The marshes of the lower portion of the bay, with higher salinity, are dominated by Spartina spp., while the marshes of the upper portion, with lower salinity, are currently composed primarily of common reed, Phragmites australis, S. alterniflora, or combinations of both. Extensive daytime sampling (n ؍ 815 tows) during May-November 1996 was conducted with otter trawls (4.9 m, 6 mm mesh) in six intertidal and subtidal marsh creek systems (upper and lower portions of each creek) where creek channel depths ranged from 1.4-2.8 m at high tide. The fish taxa of the marsh creeks was composed of 40 species that were dominated by demersal and pelagic forms including sciaenids (5 species), percichthyids (2), and clupeids (7), many of which are transients that spawn outside the bay but the early life history stages are abundant within the bay. The most abundant species were Morone americana (24.3% of the total catch), Cynoscion regalis (15.4%), Micropogonias undulatus (15.3%), Anchoa mitchilli (12.0%), and Trinectes maculatus (10.8%).
2006
The lower Chesapeake Bay and coastal ocean of Virginia serve as an important nursery area for bluefish Pomatomus saltatrix. Describing the diet composition of young-of-the-year (hereafter, age-0) bluefish in this region is essential to support current Chesapeake Bay ecosystem modeling efforts and to contribute to the understanding of the foraging ecology of these fish along the U.S. Atlantic coast. The stomach contents of 404 age-0 bluefish collected from the lower Chesapeake Bay and adjacent coastal zone in 1999 and 2000 were examined as part of a diet composition study. Age-0 bluefish foraged primarily on bay anchovies Anchoa mitchilli, striped anchovies Anchoa hepsetus, and Atlantic silversides Menidia menidia. Other fishes such as striped bass Morone saxatilis, white perch Morone americana, Atlantic menhaden Brevoortia tyrannus, and bluefish were seasonally important. Crab zoea and megalope Callinectes spp. and amphipods Gammarus spp. were the most important invertebrate prey. A seasonal dietary shift from Atlantic silversides to anchovies was evident. Overall, small pelagic and littoral schooling fishes, particularly engraulids and atherinids, predominated in the diet of the age-0 bluefish collected for this study. Although the results presented here were similar to the diet composition of age-0 bluefish reported in previous studies, some notable differences were probably due to spatial and temporal differences in prey assemblages.
A Brief Guide to Striped Bass Ecology & Management in Chesapeake Bay
2017
Currently, striped bass are not overfished and are not experiencing overfishing; however, abundance has declined since 2005. Although well-studied, future research on Chesapeake Bay striped bass should focus on the effects of disturbances that threaten the long-term sustainability of the stock. In particular, alterations and reductions in habitat quality and quantity, and long-term environmental changes associated with climate change present formidable challenges. We conclude this report with 29 recommendations for research to advance our understanding of the population biology and ecology of Chesapeake Bay striped bass.