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Full-Text Articles in Aquaculture and Fisheries
Genetic Variation In The Timing Of Gonadal Maturation And Spawning Of The Eastern Oyster, Crassostrea Virginica (Gmelin), Bruce J. Barber, Susan E. Ford, Robert N. Wargo
Genetic Variation In The Timing Of Gonadal Maturation And Spawning Of The Eastern Oyster, Crassostrea Virginica (Gmelin), Bruce J. Barber, Susan E. Ford, Robert N. Wargo
VIMS Articles
The gonadal cycles of four groups of eastern oysters, Crassostrea virginica (Gmelin), including native stocks collected that year and inbred strains (reared in Delaware Bay for 5-6 generations) from both Long Island Sound and Delaware Bay, were compared in Delaware Bay in 1987. Inbred strains resembled their respective native stocks; both Long Island groups initiated gonadal development and spawning about one month earlier and spawned over a shorter duration than both Delaware Bay groups. Analysis of covariance revealed that the effect of time on gonadal development was statistically different (P I 0.05) for all between-location group comparisons, but not for …
Temporal Variations In Spawning Behavior Of Sea Scallops, Placopecten Magellanicus (Gmelin, 1791), In The Mid-Atlantic Resource Area, James E. Kirkley, William D. Dupaul
Temporal Variations In Spawning Behavior Of Sea Scallops, Placopecten Magellanicus (Gmelin, 1791), In The Mid-Atlantic Resource Area, James E. Kirkley, William D. Dupaul
VIMS Articles
Interannual variation in spawning of Placopecten magellanicus (Gmelin) may be important to management agencies concerned with maximizing yield-per-recruit via restrictions on meat counts or temporal restrictions on catch and effort. In this study, temporal patterns in the spawning behavior of sea scallops in the Mid-Atlantic resource area for the period April 1987-April 1991 are analyzed using conventional time-series methods. Biannual spawning was found to be characteristic of sea scallops in the Mid-Atlantic resource area but was also found to be erratic in the timing, duration, and magnitude. The spring spawning event was the more predictable and dominant spawning event. The …
The Decline Of The Virginia Oyster Fishery In Chesapeake Bay Considerations For Introduction Of A Non-Endemic Species, Crassostrea Gigas (Thunberg, 1793), Roger L. Mann, Eugene M. Burreson, Patrick K. Baker
The Decline Of The Virginia Oyster Fishery In Chesapeake Bay Considerations For Introduction Of A Non-Endemic Species, Crassostrea Gigas (Thunberg, 1793), Roger L. Mann, Eugene M. Burreson, Patrick K. Baker
VIMS Articles
The Chesapeake Bay oyster fishery for Crassostrea virginica (Gmelin) is in a state of continuing decline. Two diseases, Haplosporidium nelsoni and Perkinsus marinus have effectively eliminated oysters from many sections of the Bay. Despite over 30 years of disease activity the native oysters have developed neither tolerance nor absolute resistance to these diseases, and do not exhibit any recovery in disease endemic areas in Virginia. Repletion programs have completely failed to recover to permanent production areas lost to disease. Present fishery management activities are limited to a controlled retreat away from the disease in an arena where disease distribution is …
Sterile Triploid Crassostrea Virginica (Gmelin, 1791) Grow Faster Than Diploids But Are Equally Susceptible To Perkinsus Marinus, Bruce J. Barber, Roger L. Mann
Sterile Triploid Crassostrea Virginica (Gmelin, 1791) Grow Faster Than Diploids But Are Equally Susceptible To Perkinsus Marinus, Bruce J. Barber, Roger L. Mann
VIMS Articles
Growth, tolerance of Perkinsus marinus, and gametogenesis of diploid and triploid Eastern oysters, Crassostrea virginica (Gmelin, 1791) were compared in the York River, Virginia between June 1989 and November 1990. Triploid oysters had significantly greater mean shell height (P ,a;; 0.02) and whole weight (P ,a;; 0.005) than diploid oysters throughout the study period. In November 1990, triploids had significantly greater mean dry tissue weight (P ,a;; 0.006) than diploids. On average, triploid oysters reached commercial size (63.5 mm) 5 months before diploid oysters. Diploid and triploid groups became similarly infected with P. marinus during summer 1990. Prevalences reached 96% …
Effect Of Neutral Red Stain On Settlement Ability Of Oyster Pediveligers, Crassostrea Virginica, Patrick Baker
Effect Of Neutral Red Stain On Settlement Ability Of Oyster Pediveligers, Crassostrea Virginica, Patrick Baker
VIMS Articles
The effect of neutral red stain on the settlement of oyster Crassostrea virginica (Gmelin) pediveligers was examined. Larvae were offered two types of substrate: oyster shell and acetate sheets. Settlement was measured as the proportion of pediveligers settled after 24 hours and analyzed with two-factor ANOV A. Staining did not significantly affect settlement, although settlement onto acetate was much lower than onto oyster shell.
Larvae Of Diploprion-Bifasciatum, Belonoperca-Chabanaudi And Grammistes-Sexlineatus (Serranidae, Epinephelinae) With A Comparison Of Known Larvae Of Other Epinephelines, Cc Baldwin, Gd Johnson, Pl Colin
Larvae Of Diploprion-Bifasciatum, Belonoperca-Chabanaudi And Grammistes-Sexlineatus (Serranidae, Epinephelinae) With A Comparison Of Known Larvae Of Other Epinephelines, Cc Baldwin, Gd Johnson, Pl Colin
VIMS Articles
Morphology is described for larvae of two species of the epinepheline serranid tribe Diploprionini and one of the tribe Grammistini, and known larvae of other epinephelines are compared. Early stage eggs and development of larvae of Diploprion bifasciatum are described from 144 laboratory-reared specimens, and postflexion larvae of Belonoperca chabanaudi are described from wild-caught specimens. Fourmanoir's (1976) description of postlarval Grammistes sexlineatus is modified and expanded. The second and third dorsal-fin spines of larval D. bifasciatum are remarkably elongate, reaching lengths many times that of the body. These spines are thin and flexible, and each is encased in a sheath …
Susceptibility Of Diploid And Triploid Pacific Oysters, Crassostrea Gigas (Thunberg, 1793) And Eastern Oysters, Crassostrea Virginica (Gmelin, 1791), To Perkinsus Marinus, Judith A. Meyers, Eugene M. Burreson, Bruce J. Barber, Roger L. Mann
Susceptibility Of Diploid And Triploid Pacific Oysters, Crassostrea Gigas (Thunberg, 1793) And Eastern Oysters, Crassostrea Virginica (Gmelin, 1791), To Perkinsus Marinus, Judith A. Meyers, Eugene M. Burreson, Bruce J. Barber, Roger L. Mann
VIMS Articles
The susceptibility of Pacific oysters, Crassostrea gigas, to the oyster parasite Perkinsus marinus was compared with that of eastern oysters, Crassostrea virginica, in two separate experiments. Experiments were conducted in flow-through seawater systems with quarantined effluent. Oysters were challenged by addition of infective P. marinus. In the first experiment, which used only diploid oysters, 40% of C. gigas became infected with P. marinus after 83 days compared to 100% of C. virginica. In the second experiment, which examined susceptibility of diploid and triploid individuals of both species, prevalence was high in all groups after 60 days. In …