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Acute Toxicity Potential of Chlorination in Estuarine Waters
Morris H. Roberts Jr.
Two primary uses of chlorination in estuarine systems are disinfection of sewage effluent and fouling control in condensor tubes of electric power generating plants. The intent in both uses is to apply sufficient chlorine to kill certain target organisms. At the same time, however, efforts are made to control both the application rate and effluent release so that non-target species in the receiving waters are not affected. To accomplish such control, the effluent is usually retained, which permits the decay of the residual chlorine and rapid dilution with ambient water to reduce further the residual. The residual concentration continues to decay in the ambient water through a series of reactions outlined in Dr. Helz's paper. If all goes well, no adverse impacts can be expected in the receiving waters.
However, ·at least two disquieting instances of chlorination's possible impact in the Chesapeake Bay have been observed.
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A study of the Present State of Oyster Statistics in Chesapeake Bay and Suggested Remedial Measure
George E. Krantz and Dexter S. Haven
Accurate, detailed and timely information on oyster landings are essential to the efficient management of the oyster resources of Chesapeake Bay. Basic types of i_nformation needed are volumes of oysters harvested on: a) designated public beds; b) unassigned bottoms; and c) leased areas. These data need to be as site specific as possible and include the type of harvest gear. Moreover, it is essential to know the portion of harvest which results from state repletion activities (planted shells or seed) and that part originating from natural production. Price, method of harvest, the buyers and sellers identifi_cation, and other similar data are also needed. However, there are today several major problems in the collections of accurate oyster statistics in the Chesapeake Bay region. Accurate oyster statistics are not being collected. Part of the reason for this is that the data base is oriented toward tax collection rather than the collection of biological statistics about the oyster population.
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Blue crab mortalities associated with pesticides, herbicides, temperature, salinity, and dissolved oxygen
Willard A. Van Engel
Commercial fisheries landings of the blue crab in the Chesapeake Bay have fluctuated widely since the late 1920s (Figure I). Records of annual landings prior to 1929 are sparse and permit little more than a guess of trends, although a discontinuous series of catch records from 1907 to 1926 from individual watermen, on file at the Virginia Institute of Marine Science (VIMS), may provide sufficient baseline data for interpretations or estimates of trends in the early period.
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Distribution and Abundance of Submerged Aquatic Vegetation in Chesapeake Bay
Robert J. Orth and Kenneth A. Moore
The Chesapeake Bay, with its extensive littoral zone and broad salinity regime of Oto 25 ppt, supports many different species of submerged aquatic vegetation (SAV) (Anderson 1972, Stevenson and Confer 1978, Orth et al. 1979). Approximately ten species of submerged vascular plants are abundant in the Bay, with another ten species occurring less frequently. In many areas, more than one species is found in a particular bed of SAV because of the similarity in the physiological tolerances of some species. Between regions of the Bay, salinity appears to be the most important factor in controlling the species composition of an individual bed of SAV (Stevenson and Confer 1978), while sediment composition and light regime are important factors in controlling the distribution of SAV within regions of the Bay. All species, regardless of the salinity regime, are found in regions of the Bay's littoral zone and are iocated in water less than two to three meters deep (mean low water - MLW), primarily because of low levels of light that occur below these depths (Wetzel et al. 1981).
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Finfisheries Problems and Approaches
John V. Merriner and Harley J. Spier
The fisheries data of principal concern at this conference are those which provide an accurate description of the harvest from the resource. Most often, one thinks of the "standard" reference fishery data from commercial fish landings: pounds by species, dockside dollar value, location of the catch, gear used, and number of fishermen. These data have been widely used by biologists and managers to evaluate the status of particular stocks and trends in the fishery. An example of a recent evaluation for Chesapeake Bay fisheries is Rothschild et ·a1. (1981). Several underlying truths must be borne in mind when discussing territorial seas fisheries management and the statistical database.
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Life history, ecology and stock assessment of the blue crab Callinectes sapidus of the United States Atlantic Coast - a review
Robert E. Harris
The blue crab is found along the Atlantic coast of the United States from Maine to southern Florida. It is uncommon north of Cape Cod and is most abundant in the Chesapeake Bay where almost half of the United States commercial blue crab landings occur.
The Chesapeake Bay has the largest semi-confined area for blue crab spawning, more nursery area and probably the best mix of environmental conditions for blue crab along the United States eastern coast. In addition, an intensive commercial fishery enables the Chesapeake Bay region to be the area of highest blue crab production.
There are many basic similarities in the life history of the blue crab all along the Atlantic coast. Some differences do occur, however, in timing of some of the life processes, probably due to the different temperature regimes that exist along the coast.
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Light and Submerged Macrophyte Communities in Chesapeake Bay: A Scientific Summary
Richard L. Wetzel, Robin F. van Tine, and Polly A. Penhale
The initial focus of submerged aquatic vegetation (SAV) research in the U.S. Environmental Protection Agency (EPA), Chesapeake Bay Program (CBP) was evaluation of the structural and functional ecology of these communities. In the upper Bay, Myriophyllum spicatum and Potamogeton perfoliatus are the dominant species; the dominant species in the lower Bay are Zostera marina and Ruppia maritima. Studies centered on various aspects of productivity (both primary and secondary), trophic structure, and resource utilization by both ecologically and economically important species. Much of the initial research was descriptively oriented because of a general lack of information on Chesapeake Bay submerged plant communities. These investigations created the data base necessary for the development of ecologically realistic simulation models of the ecosystem. Following these initial studies, the research programs in both Maryland and Virginia evolved toward more· detailed analyses of specific factors ~hat potentially limit or control plant growth and productivity. Previous results indicated certain environmental parameters and biological processes that possibly limited and controlled SAV distribution and abundance. Specifically, these included light, nutrients, herbicides and fouling (epibiotic growth). Laboratory and field studies were devoted in the later phases of the CBP-SAV program toward investigating these interactions. This work is among the first studies in North America to investigate light quality as a major environmental factor affecting the survival of sea grasses.
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Pertintent Statistical Data for the Management of Maryland and Virginia Fisheries
Philip W. Jones and Joseph Loesch
Statistical records of the cpmmercial fisheries of Chesapeake Bayl, which have been compiled periodically since 1887 and annually since 1929, are the basis of our historical knowledge of commercial landings and fishing effort in Maryland and Virginia waters. The primary purpose of collecting commercial fisheries statistics has been to determine the number of fishermen, gear, and boats in the commercial fishery, and the total weight of each species landed. Prior to 1944, these statistics were estimated for both Maryland and Virginia fisheries from correspondence or interviews between federal and state personnel and large-scale commercial fishing operations, representative watermen, captains of licensed fishing vessels, wholesale fisheries firms, and packing and canning houses. ... more
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The Blue Crab Fisheries in the Chesapeake Bay Problems and Approaches
W. A. Van Engel, C. F. Bonzek, and Ray Dintaman
Regulations of the blue crab (Calinectes sapidus) fishery in the Chesapeake Bay have been based on empirical reasoning involving biological, economic, political and sociological considerations. These regulations cover licensing, size and sex limits, quotas, seasons, and gear restrictions. They are designed to promote utilization of the resource for near maximum production, a reasonable economic return from adequate catch per unit of effort, and orderly fishing to minimize conflicts between units and types of gear.
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The Chesapeake Bay Fisheries A Scientific Perspective
Hubert M. Austin
Fisheries science plays a dual role in support -of management of living marine resources. A fisheries scientist is an advisor to a local, state, regional, national or international fisheries management or regulation agency, providing scientific information on the living marine resource to the agency so that informed decisions may be made. As such, scientific data, analyses, and information can have a significant impact on the socio-economic wellbeing of major segments of the population, as well as on the viability of the fishery stock. This information must be drawn from critical scientific analyses of data, the output from field assessment programs, catch statistics, and mathematicql models of varying degrees of sophistication. ... more
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The Hard Clam Fishery Problems and Approaches
Andre C. Kvaternik and William D. DuPaul
The hard clam, Mercenaria mercenaria (Linne, 1758), is a euryhaline bivalve found along the eastern and Gulf coasts of North America (Abbott 1954, Carriker, 1961; Wass, 1972, Miller et al., 1975). It is an important commercial bivalve along the Atlantic Coast (Belding, 1912; Tiller et al., 1952; Andrews, 1970; Castagna and Haven, 1972; McHugh, 1972, 1977, 1982; Miller et al., 1975). Hard clams are consumed in a wide variety of ways, with the larger clams (>80 nun) being used in chowder and the smaller and more succulent littlenecks (< 60 nun) ("necks") and cherrystones (61-80 rrm) ("cherries") being eaten either steamed or raw on the half shell. The fishery for hard clams in the Chesapeake Bay is presently only understood on a broad scale. ... more..
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Toxic Substances
R. Bieri, O. Bricker, R. Byrne, R. J. Diaz, and et al
This part of the CBP Synthesis Report summarizes and integrates the research findings and reconnnendations of 13 projects of the Chesapeake Bay Toxic Substances Program performed between July 1978 and October 1981. The following sections describe research on potentially toxic substances, or toxicants, in water-sediments and selected biota. The subjects considered include a brief review of metals, their sources, distribution and behavior, and then a review of sources and distribution of organic chemicals. Finally, information concerning the significance of toxicants in the- Bay and their pattern of enrichment is provided. Most information synthesized in this report can be traced to its origin in scientific project reports listed in Appendix A.
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Bacterial Biomass And Heterotrophic Potential in the Waters of the Chesapeake Bay Plume and Contiguous Continental Shelf
Howard I. Kator and Paul L. Zubkoff
Bacterial populations in Chesapeake Bay and contiguous shelf waters are significant to such essential processes as mineralization, nutrient recycling, degradation of pollutants and biomass production. However, our understanding of such dynamic relationships of physical and chemical factors to bacterial biomass and activities in Chesapeake Bay plume waters is limited. The availability of synoptic hydrographic (and remotely sensed physical-chemical) data obtained simultaneously with measurement of of microbial biomass and activity presented an opportunity to examine such relationships.
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Chesapeake Bay Plume Dynamics from LANDSAT
John C. Munday Jr. and Michael S. Fedosh
Examination of 81 dates of Landsat images with enhancement and density slicing has shown that the Chesapeake Bay plume usually frequents the Virginia coast south of the Bay mouth. Southwestern (compared to northern) winds spread the plume easterly over a large area. Ebb tide images (compared to flood tide images) show a more dispersed plume. Flooding waters produce high turbidity levels over the shallow northern portion of the Bay mouth.
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Nonpoint sources and impacts in a small coastal plain estuary: a case study of the Ware River basin, Virginia
Gary F. Anderson and Cindy Bosco
The Ware River Study is one of five small watershed projects sponsored by the EPA Chesapeake Bay Program. These projects are designed to provide data on nutrient and organic loadings entering the Bay over the wide range of topographies, climates, and land uses which occupy its watershed. Each provides information on a particular geographic segment of the Bay region. In particular, the Ware study is intended to document special characteristics of runoff from low relief coastal plain environments, and to document their impacts on a small estuarine receiving water.
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Temporal And Spatial Variations Of The Chesapeake Bay Plume
Evon P. Ruzecki
Historical records and data obtained during the Superflux experiments are used to describe the temporal and spatial variations of the effluent waters of Chesapeake Bay. The alongshore extent of the plume resulting from variations of fresh water discharge into the Bay and the effects of wind are illustrated. Variations of the cross-sectional configuration of the plume over portions of a tidal cycle and results of a rapid-underway water sampling system are discussed.
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Distribution and Hydrodynamic Properties of Fouling Organisms in the Pier 12 Area of the Norfolk Area Station
Robert J. Diaz
Fouling of deep draft naval vessels, in particular aircraft carriers, in the area of the Norfolk Naval Station has been a reoccurring problem since the early 60's. The principal agents of fouling have been the hydroid, Sertularia argentea and the fleshly bryozoan, Alcyonidium verrilli. The particular fouling problem encountered in the Norfolk area is not the typical case of the organisms growing attached to ship hulls but is basically a problem of sea suction and subsequent clogging of screen grates and condenser tube sheets.
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Evaluating impacts on continental shelf environments, concepts and prospects
Donald F. Boesch
New and expanding activities on the continental shelf including disposal of wastes and dredged material, deepwater ports, floating nuclear power plants, mining, and oil and gas exploitation, have spawned increased interest in the ecology of continental shelf ecosystems and the environmental effects of these activities. Changing patterns of historical uses of the shelf environment, i.e., fishing and transportation, and as yet hypothetical new uses, such as tapping energy from the ocean's currents and gradients, will undoubtedly further increase our concern for the coastal oceans.
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Coliform Depuration Of Chesapeake Bay Oysters
Dexter S. Haven, Frank O. Perkins, Reinaldo Morales-Alamo, and Martha W. Rhodes
Oysters contaminated in nature depurated fecal coliforms to levels below 50/100 g in 48 hr over a wide range of environmental conditions typical of the lower Chesapeake Bay region. Temperature was found to be the most crilical environmental factor with conditions below 10-12°C having the potential of inhibiting depuration. Coliform clearance did not appear to be correlated with pumping rate or biodeposition activity of oysters. Oysters infected with the pathogens Dermocystidium marinum and Minchinia nelsoni (MSX) depurated as rapidly as uninfected ones. Meat quality and size of oysters likewise did not affect depuration.
Four commercial-size tanks of different designs were found to yield satisfactory results in 48 hr. Water flow rates over the ranges studied and location of trays within the tanks did not influence depuration.
Biodeposits contained high levels of total and fecal coliforms, but their accumulation in the tanks did not have a detrimental effect under the conditions studied.
Pooling oysters during monitoring of' depuration samples was necessary due lo the variation of coliform levels in individual oysters. Samples of 6-8 pooled oysters appeared to be adequate for estimating coliform levels.
The Medium A-1 test was superior to the elevated temperature coliform plate_ (ETCP) procedure of Cabelli and Heffernan for determination of fecal coliforms in oysters.
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Freshwater and Marine Fishes
Robert E. Jenkins
The current list of freshwater fishes known from Virginia stands at 206 species, including 10 that are diadromous and 4 others ranked as freshwater-estuarine. Eight of the freshwater and one of the freshwater-estuarine species were introduced to the state. Several additional strictly freshwater fishes are expected to be discovered. The Virginia freshwater ichthyofauna is relatively rich in species compared with most other states. For example, Maryland and Delaware together have 99 species (Lee et aZ., 1976), West Virginia 151 (Denoncourt et aZ., 1975), Kentucky 201 (Clay, 1975), and North Carolina 195 (Menhinick et aZ., 1974). Some of these totals reflect our adjustments for diadromous and estuarine fishes. The other adjacent state, Tennessee has a much richer freshwater fauna than Virginia. <.....>
Virginia's marine and estuarine fish fauna is characterized by its dynamic nature. Most elements of the fauna are migratory. All are highly mobile. Most are widespread coastally and occur in their preferred habitats in many localities within Virginia and other states. Musick (1972) annotated 208 species of marine and estuarine fishes within Virginia's coastal fish fauna, including 174 marine, 24 estuarine, and 10 diadromous (9 anadromous, 1 catadromous) species. Fourteen (10 diadromous and 4 estuarine) species are shared with the freshwater faunal list.
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Kepone® Residues In Chesapeake Bay Biota
M. E. Bender, R. J. Huggett, and W. J. Hargis Jr.
Oysters from the James displayed variations in Kepone residue levels related to water temperature and their spawning cycle. Oyster depuralion rates were related to temperature. In summer the "biological half. life" of Kepone in oysters was about one week, while during the winter about 40 days were required for residue levels to decline by 50 per cent. Residues in blue crabs varied as a function of sex, males having considerably higher residues than females. Fin fish levels from the James varied greatly, with residue levels being dependent on species and length of residence for migratory fishes .. Average Kepone residues in freshwater fish species, which are resident their entire Jives, varied from 0.04 to 2.4 μg/g. Long-term resident estuarine fin fish varied less than freshwater species, with mean concentrations between 0.6 and 2.7 μg/g. Short-term resident marine fish species, e.g. American shad and menhaden, exhibited low residues averaging less than 0.1 μg/g, while spot and croaker, which reside in the river for longer periods, bad higher residues averaging 0.81 and 0.75 μg/g respectively.
In the Bay, croaker, spot, trout and flounder all exhibited similar residue patterns showing lower residue levels at stations further up-Bay from the Kepone source in the James River.
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Marine Invertebrates
Marvin L. Wass
Virginia and Maryland are favored with the largest estuary in the United States-the Chesapeake Bay. The Bay is 289 kilometers (173 miles) long and 47.6 kilometers (28.6 miles) wide near Smith Point. The estuary is relatively shallow, with an average depth of 8.05 meters (26.4 feet) and a maximum depth of 53 meters (174 feet) at Blood Point Light in Maryland. The greatest depth in Virginia is near Smith Point: 44 meters (144 feet) (Wolman, 1968). While this deep hole has probably never been sampled for benthos, many rare species have been collected in an area just south of Smith Point (Figure 1).
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Proceedings of Workshop on Soft Shell Blue Crabs : September 22, 1979, Charleston, South Carolina
David M. Cupka and Willard A. Van Engel
The Workshop on Soft Shell Blue Crabs was held on September 22, 1979 at the Marine Resources Center of the South Carolina Wildlife and Marine Resources Department in Charleston, South Carolina.
The purposes of the workshop were to describe current research and development activities relative to soft shell blue crabs in the Coastal Plains Region; to review existing laws and regulations in regards to soft shell crab fisheries and shedding operations; and to discuss methods for harvesting, handling, shedding and marketing soft shell blue crabs.
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The Marine Algae of Virginia
Harold J. Humm
Starting with initial collections near Yorktown back in 1946, Humm over the years gathered information on algae appearing all seasons of the year from bays, marshes, reefs, wrecks and a variety of substrates from the Eastern Shore, Chesapeake Bay and tidewater areas.
Includes a systematic list of species, keys, descriptions, drawings and images of specimens.
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Beach Zone Fish Community Structure In The James River, Virglnia
Douglas W. Lipton and Jack G. Travelstead
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.
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Depuration Of Kepone By Atlantic Croaker In A Laboratory Study
Robert T. Doyle, J. V. Merriner, and M. E. Bender
Contamination of the James River in Virginia by the organochlorine pesticide Kepone R prompted depuration studies of commercially important species. Approximately 400 croaker (Micropogonias undulatus) were taken from the James River and placed in Kepone-free York River water. Groups of 20 fish, maintained at ambient temperature, were sampled over time to determine depuration rate. Results suggest that there is no substantial depuration of Kepone by croaker until water temperature exceeds 15 C.
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Deterioration Of Floy fd-67 Internal Anchor Tags
M. Y. Hedgepeth, W. H. Kriete Jr., and J. V. Merriner
Yellow Floy FD-67 internal anchor tags were utilized in an experimental and field study of tag discoloration, tag legibility and fouling organisms. Most tags exhibited some degree of discoloration over time. The rate and extent of discoloration varied between two batches of tags purchased in different years. The legibility of a tag was not affected to a great extent by the degree of discoloration. Legends of some completely discolored tags were still readable. Fouling organisms eroded the vinylite covering and deteriorated the legends of some tags. Bryozoans, barnacles and tunicates were the most commonly encountered fouling organisms. Barnacles were the most erosive of these organisms. Other causes of tag discoloration were believed to be chemical reactions between the vinylite covering and environmental factors such as salt concentration.
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Growth And Survival Of Striped Bass And Striped Bass X White Perch Hybrids
J. Howard Kerby and Edwin B. Joseph
Experiments comparing growth and survival of striped bass (Morvne saxatilis) and striped bass female X white perch (M. americana) male hybrids indicated the hybrids were hardier than striped bass under the same experimental conditions. Striped bass exhibited health problems and resulting mortality which were not evident in the hybrids. Overall survival of striped bass in 2 replicate experiments was 42.5% after II months. whereas that of the hybrids was 84.2%. Striped bass and hybrid growth patterns were similar, but striped bass grew somewhat more rapidly than the latter. Mean specific (instantaneous) growth rates were roughly similar throughout the study. with the major differences occurring during the first 4 months. At 17 months of age the mean hybrid fork length was 227.50101 (range. 167 to 282 0101). This length was approximately equivalent to that of wild populations of white perch with 4 to 8 annuli and to that of mid-Atlantic striped bass with 2 annuli, but was substantially less than that of fresh-water and more southern populations. Hybrid length-weight equations were intermediate between those of striped bass and white perch. Salinity experiments demonstrated that both small (mean fork length, 43 mm) and large (mean fork length. 279 mm) hybrids can survive and grow for indefinite periods at salinities of 18 to 25 0/00 with no signs of stress. We believe that the hybrid may be suitable as a supplement to natural populations of striped bass and white perch in estuaries.
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Modeling sediment movement in the turbidity maximum of an estuary
Allbert Kuo, Maynard M. Nichols, and James Lewis
This research developed a two-dimensional, time-dependent numerical model to simulate the movement of water and suspended sediment in the turbidity maximum of an estuary. This model is a systematic sequence of mathematical procedures derived from the mass-balance equation and the equation of motion. Lateral integration is used to obtain two-dimensional equations; these equations are integrated with depth over the height of successive layers. Finite difference equations then are written for each layer and solved numerically using prescribed boundary conditions.
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Movement Of 1970 Year Class Striped Bass Between Virginia, New York And New England
William H. Kriete Jr., John V. Merriner, and Herbert M. Austin
Striped bass (Marone saxatilis) were tagged in Virginia beginning in 1968. The 1970 yearclass of striped bass was tagged both in Virginia and New York in 1972. Fish tagged in Virginia were returned from New York to Maine while fish tagged in New York were returned from the Maryland portion of the Chesapeake Bay and the Potomac River. These data indicated that fish migrate from rivers in which they were spawned at different ages and that fish that migrate as 2 year olds remain together as a group until they are 3+ years. Therefore, within the Chesapeake Bay area there are distinct river populations at least until these populations are 3+ years old.
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