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Full-Text Articles in Life Sciences
Eastern Atlantic Tonguefishes (Symphurus: Cynoglossidae, Pleuronectiformes), With Descriptions Of Two New Species, Thomas A. Monroe
Eastern Atlantic Tonguefishes (Symphurus: Cynoglossidae, Pleuronectiformes), With Descriptions Of Two New Species, Thomas A. Monroe
VIMS Articles
Six species of symphurine tonguefishes, including two previously undescribed, from the Mediterranean Sea and eastern Atlantic Ocean (including the Azores, Madeira, Ascension, and St. Helena) are described and illustrated.
Systematics Of The Pearlfishes (Pisces, Carapidae), Df Markle, Je Olney
Systematics Of The Pearlfishes (Pisces, Carapidae), Df Markle, Je Olney
VIMS Articles
A review of taxonomy, anatomy, ontogeny, ecology, and phylogeny of the ophidiiform family Carapidae was conducted using over 2,300 larval, juvenile and adult specimens. A cladistic classification based on swimbladder morphology, developmental and osteological characters of the vertebral column, fins, pectoral and pelvic girdles, gill arches, ethmoid, jaws, and habitat is presented. A total of 31 species (6 new names and one unnamed larval form) in seven genera are recognized in two subfamilies. A species previously assigned to Echiodon is made the type of a new monotypic genus. Species of the tribe Carapini are rearranged in the genera Carapus and …
Settlement Of Oysters, Crassostrea Virginica (Gmelin, 1791), On Oyster Shell, Expanded Shale And Tire Chips In The James River, Virginia, Roger L. Mann, Bruce J. Barber, James P. Whitcomb, Kenneth S. Walker
Settlement Of Oysters, Crassostrea Virginica (Gmelin, 1791), On Oyster Shell, Expanded Shale And Tire Chips In The James River, Virginia, Roger L. Mann, Bruce J. Barber, James P. Whitcomb, Kenneth S. Walker
VIMS Articles
The effectiveness of oyster shell, expanded shale, and tire chips as substrates for settlement of oysters, Crassostrea virgi11ica (Gmelin), was compared at four locations in the James River, Virginia, over three two-week time intervals in August and September, 1988. Only differences between substrate were significant (P < 0.001). Over all locations and time intervals, a significantly higher (P < 0.001) proportion of total oyster settlement occurred on oyster shell (63.8%) than on either tire chips (22.1 %) or expanded shale (14.2%).
Recruitment And Growth Of Oysters On Shell Planted At Four Monthly Intervals In The Lower Potomac River, Maryland, Reinaldo Morales-Alamo, Roger L. Mann
Recruitment And Growth Of Oysters On Shell Planted At Four Monthly Intervals In The Lower Potomac River, Maryland, Reinaldo Morales-Alamo, Roger L. Mann
VIMS Articles
Oyster shells were planted on four successive months (May to August 1986) in contiguous plots at Jones Shore Bar in the Potomac River, Maryland, to study the effect of differences in time of cultch planting on settlement and survival of oyster spat. The plots were usually sampled at two-week intervals from time of planting through November, 1986, and once in June, 1987. A massive concentration of the tunicate Molgula manhattensis covered the bottom in all plots within four to six or eight weeks following shell planting. A commercially acceptable number of spat per shell, between 1.8 and 2.2 (approximately equivalent …
Development Of The Reproductively Functional Form In The Male Blue-Crab, Callinectes-Sapidus, Wa Van Engel
Development Of The Reproductively Functional Form In The Male Blue-Crab, Callinectes-Sapidus, Wa Van Engel
VIMS Articles
The progression of the morphological features of the male blue crab reproductive system that culminate in puberty involves one change in the gonad, four combinations of the method and degree of adherence of the abdomen to the sternum, four variations in the positions of the penes, and four variations in the positions of the pleopods. The sequence of development appears to be established: (I) spennatophores must be present in the anterior vasa deferentia; (2) the abdomen must be completely free of the sternum, or, in addition, may be locked by the sternal tubercles; (3) and the penes and second pleopods …
Seasonal Composition Of Finfish In Waters Behind The Virginia Barrier Islands, Brenda L. Norcross, David Hata
Seasonal Composition Of Finfish In Waters Behind The Virginia Barrier Islands, Brenda L. Norcross, David Hata
VIMS Articles
Semi-monthly sampling of finfish was conducted in the lagoons and marshes behind Parramore and Cedar Islands at Wachapreague Inlet, Cobb and Wreck Islands at Sand Shoal Inlet, and on the northwest side of Fisherman Island from September 1986 through September 1987. Although all lifestages were collected, the study was designed to focus on utilization of this area by juvenile finfish. Sixty-nine species offinfish were collected. Species diversity and abundance fluctuated widely among seasons. Both were highest in the fall and lowest in the winter. The most abundant species over all seasons and locations were silversides (Menidia menidia) and bay anchovy …
Blue-Crab Population-Dynamics In Chesapeake Bay - Variation In Abundance (York River, 1972-1988) And Stock-Recruit Functions, Rom Lipcius, Wa Van Engel
Blue-Crab Population-Dynamics In Chesapeake Bay - Variation In Abundance (York River, 1972-1988) And Stock-Recruit Functions, Rom Lipcius, Wa Van Engel
VIMS Articles
Blue crab abundance in the York River, Virginia was analyzed for interannual, monthly and spatial variation at two stations sampled by bottom trawl from 1972-1988. Various stock-recruitment and recruit-stock functions were derived from trawl abundance and commercial fishery landings statistics. The key component of variation was due to interannual fluctuations in abundance, which remained consistently high or low for two or more years before changing, suggesting internal population feedback mechanisms, such as cannibalism, or long-term climatic control. In addition, significant cyclic patterns in residuals from stockrecruitment functions further indicated the existence of long-term variability in abundance. Peak seasonal abundance and …
Foraging Behavior Of The Blue-Crab, Callinectes-Sapidus, On Juvenile Oysters, Crassostrea-Virginica - Effects Of Prey Density And Size, Db Eggleson
VIMS Articles
Blue crabs (Callinectes sapidus) are major predators of juvenile oysters (Crassostrea virginica) in Chesapeake Bay, yet little information exists on the foraging behavior and predatorprey dynamics for this predator-prey system. Laboratory experiments assessed functional responses of blue crabs to six densities of three size-classes of juvenile American oysters. Behavioral subcomponents of the crabs' functional response were quantified: total and successful encounter rates, proportional attack success, persistence time in unsuccessful encounters, and breaking, eating and handling times in successful encounters. Specific opening techniques were used by crabs for the three oyster size-classes. Blue crabs exhibited a hyperbolic type II functional response …
Molting In The Mature Female Blue-Crab, Callinectes-Sapidus Rathbun, Kirk J. Havens, Jr Mcconaugha
Molting In The Mature Female Blue-Crab, Callinectes-Sapidus Rathbun, Kirk J. Havens, Jr Mcconaugha
VIMS Articles
The present study examined the hypothesis that mature female blue crabs, Callinectes sapidus, do not enter a terminal anecdysis. Induced molting via eyestalk ablation, size frequency distributions, gonad development and limb regeneration indices from field collected animals are used as indicators of potential post maturity molts. Eyestalk ablation of 15mature females resulted in ecdysis in II individuals approximately 51 days (standard error = 0.64) after ablation, indicating a physiological ability of mature females to complete ecdysis. Analysis of size frequency distributions from catch data indicated two distinct shifts from smaller to larger females, one in early spring and a second …
Daily, Monthly And Annual Settlement-Patterns By Callinectes-Sapidus And Neopanope-Sayi Megalopae On Artificial Collectors Deployed In The York River, Virginia - 1985-1988, J Van Montfrans, Ca Peery, R J. Orth
Daily, Monthly And Annual Settlement-Patterns By Callinectes-Sapidus And Neopanope-Sayi Megalopae On Artificial Collectors Deployed In The York River, Virginia - 1985-1988, J Van Montfrans, Ca Peery, R J. Orth
VIMS Articles
Daily, monthly and annual settlement of dominant brachyuran megalopae on six replicate artificial settlement substrates (collectors) was examined at one site in the York River, Virginia, from mid-July or early August to early December during 1985-1988. Callinectes sapidus Rathbun, an exported estuarine species, and Neopanope sayi (Smith), a retained estuarine species, were the numerically dominant colonizers of collectors. C. sapidus settlement was highly episodic (l-3-day duration) and significantly associated with the full moon period (lunar day 15-22). The temporal mean of settlement for C. sapidus each year fell within a 12-day period (24 September-6 October) over the 4 years. C. …
Settlement Patterns Of Crassostrea Virginica (Gmelin, 1791) Larvae In Relation To Tidal Zonation, G. Curtis Roegner, Roger L. Mann
Settlement Patterns Of Crassostrea Virginica (Gmelin, 1791) Larvae In Relation To Tidal Zonation, G. Curtis Roegner, Roger L. Mann
VIMS Articles
Experiments were conducted to determine the settlement distribution of the oyster Crassostrea virginica (Gmelin) in relation to tidal zonation in an area where adult populations are largely confined to the intertidal zone. Hatchery-reared pediveliger larvae were interned in PVC tubes positioned at known tidal heights. The influence of non-tidal factors was limited: mesh covering the ends of the tubes prevented loss of larvae to dispersal or predation, the settling substrate was not colonized by competitors, and the effects of light and horizontal currents were minimized. Settlement was found to occur throughout the intertidal zone but predominated at the bottom of …
Biochemical Genetics Of Southern California Basses Of The Genus Paralabrax - Specific Identification Of Fresh And Ethanol-Preserved Individual Eggs And Early Larvae, John Graves, Michelle J. Curtis, Paul A. Oeth, Robin S. Waples
Biochemical Genetics Of Southern California Basses Of The Genus Paralabrax - Specific Identification Of Fresh And Ethanol-Preserved Individual Eggs And Early Larvae, John Graves, Michelle J. Curtis, Paul A. Oeth, Robin S. Waples
VIMS Articles
No abstract provided.
Stomach Contents And Parasite Infestation Of School Bluefin Tuna Thunnus-Thynnus Collected From The Middle Atlantic Bight, Virginia, David B. Eggleston, Eleanor A. Bochenek
Stomach Contents And Parasite Infestation Of School Bluefin Tuna Thunnus-Thynnus Collected From The Middle Atlantic Bight, Virginia, David B. Eggleston, Eleanor A. Bochenek
VIMS Articles
No abstract provided.
Differential Growth Among Cohorts Of Age-0 Weakfish Cynoscion-Regalis In Chesapeake Bay, Stephen T. Szedimayer, Mp Weinstein, John A. Musick
Differential Growth Among Cohorts Of Age-0 Weakfish Cynoscion-Regalis In Chesapeake Bay, Stephen T. Szedimayer, Mp Weinstein, John A. Musick
VIMS Articles
Age-0 weakfish Cynoscion regalis, were sampled from the Chesapeake Bay-York River estuary in 1983 and 1984 to test for the existence of multiple cohorts and compare growth rates. In both years juveniles were first collected in the estuary in late July, were significantly more abundant from August to mid-October, but were uncommon by the end of October. Significantly more weakfish were collected in 1983 than in 1984. Daily ages were determined based on scale circuli. Cohorts were separated by local minima in birthdate distributions: cohort 1 hatched before 16 July 1983, cohort 2 (16 July-15 August 1983), cohort 3 (15 …
Shelter Scaling Regulates Survival Of Juvenile Caribbean Spiny Lobster Panulirus Argus, Db Eggleston, Rom Lipcius, Dl Miller, L Cobacetina
Shelter Scaling Regulates Survival Of Juvenile Caribbean Spiny Lobster Panulirus Argus, Db Eggleston, Rom Lipcius, Dl Miller, L Cobacetina
VIMS Articles
No abstract provided.
Planktonic Availability, Molt Stage And Settlement Of Blue Crab Postlarvae, Rom Lipcius, Ej Olmi, J Van Montfrans
Planktonic Availability, Molt Stage And Settlement Of Blue Crab Postlarvae, Rom Lipcius, Ej Olmi, J Van Montfrans
VIMS Articles
No abstract provided.
Variation In Planktonic Availability And Settlement Of Blue-Crab Megalopae In The York River, Virginia, Ej Olmi, J Van Montfrans, Rn Lipcius, R J. Orth, Pw Sadler
Variation In Planktonic Availability And Settlement Of Blue-Crab Megalopae In The York River, Virginia, Ej Olmi, J Van Montfrans, Rn Lipcius, R J. Orth, Pw Sadler
VIMS Articles
Blue crab, Callinectes sapidus, megalopae and juveniles were sampled in the plankton and on natural (grassbeds) and artificial settlement substrates (collectors) at two sites in each of two areas of a lower Chesapeake Bay tributary (York River, Virginia) to examine spatial variability in blue crab recruitment. Spatial patterns of abundance were not consistent across habitats (plankton, artificial collectors and grassbeds) or time. Densities of planktonic megalopae were homogeneous at 1-2 m (within site) but varied at spatial scales of hundreds of meters (between sites) and kilometers (between areas). Settled megalopae were distributed unevenly within and between sites, but their abundance …
Automated Enumeration By Computer Digitization Of Age-0 Weakfish Cynoscion Regalis Scale Circuli, Stephen T. Szedlmayer, Margaret M. Szedlmayer, Michael E. Sieracki
Automated Enumeration By Computer Digitization Of Age-0 Weakfish Cynoscion Regalis Scale Circuli, Stephen T. Szedlmayer, Margaret M. Szedlmayer, Michael E. Sieracki
VIMS Articles
There has been extensive use of daily otolith growth increments in age and growth ·studies of age-O fishes (Campana and Neilson 1985). Recently, the daily ageing method has been extended to scales (Szedlmayer et al. In press). However, visually counting increments is tedious, time consuming, and subject to human error (Rice 1987). In an effort to automate the counting of increments or daily circuli in scales of age-O juvenile weakfish Cynoscion regalis, a microcomputer-based system was used to digitize the video image of a scale, store the light intensities from a radial transect, and count circuli.
Effect Of Decreasing Oxygen Tension Of Swimming Rate Of Crassostrea Virginica (Gmelin, 1791) Larvae, Roger L. Mann, Julia S. Rainer
Effect Of Decreasing Oxygen Tension Of Swimming Rate Of Crassostrea Virginica (Gmelin, 1791) Larvae, Roger L. Mann, Julia S. Rainer
VIMS Articles
Four sizes of Crassostrea virginica Gmelin larvae (mean lengths 76.8, 118.1, 139.7 and 290.2 [Lm) were exposed to ·stepwise decreases in oxygen concentration from I 00% saturation (5 .38 mill at 22°C and 22 ppt salinity) to as low as 10% saturation and their swimming rates (net vertical movement per unit time) were recorded at each oxygen concentration. No cessation of swimming was observed and in only two conditions, that of 76.8 [Lm larvae at 10% saturation and 290.2 j.Lm larvae at 21% saturation, was swimming rate significantly lower than that of the same size larvae at full saturation.