Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Marine Biology (380)
- Animal Sciences (170)
- Aquaculture and Fisheries (164)
- Ecology and Evolutionary Biology (49)
- Microbiology (41)
-
- Physical Sciences and Mathematics (40)
- Environmental Microbiology and Microbial Ecology (37)
- Environmental Sciences (22)
- Terrestrial and Aquatic Ecology (22)
- Oceanography and Atmospheric Sciences and Meteorology (18)
- Oceanography (15)
- Biology (4)
- Climate (4)
- Other Ecology and Evolutionary Biology (3)
- Zoology (3)
- Biogeochemistry (2)
- Earth Sciences (2)
- Education (2)
- Environmental Health (2)
- Pharmacology, Toxicology and Environmental Health (2)
- Science and Mathematics Education (2)
- Agricultural Economics (1)
- Agriculture (1)
- Biodiversity (1)
- Botany (1)
- Diseases (1)
- Environmental Monitoring (1)
- Evolution (1)
- Immunology and Infectious Disease (1)
- Publication Year
Articles 481 - 510 of 592
Full-Text Articles in Life Sciences
Stratigraphic Consistency And The Shape Of Things, Me Siddall
Stratigraphic Consistency And The Shape Of Things, Me Siddall
VIMS Articles
Huelsenbeck (1994) identified three unsolved issues regarding the use of temporal information in the fossil record: (1) how goodness of fit between stratigraphy and phylogeny should be determined, (2) how the significance of this fit should be determined, and (3) how those results might be employed other than for description. With respect to goodness of fit, Huelsenbeck (1994) suggested that his stratigraphic consistency index (SCI) was both intuitively simple and not subject to the biases inherent in other stratigraphic indices. With respect to these prior indices (Gauthier et ai., 1988; Norell and Novacek, 1992), apparent biases are the result of …
Phylogenetic Covariance Probability: Confidence And Historical Associations, Me Siddall
Phylogenetic Covariance Probability: Confidence And Historical Associations, Me Siddall
VIMS Articles
The correlation that exists among multiple cladograms is often taken as evidence of some underlying macroevolutionary phenomenon common to the histories of those clades and, thus, as an explanation of the patterns of association of the constituent taxa. Such studies have various forms, the most common of which are cladistic biogeography and host-parasite coevolution. The issue of confidence has periodically been a theoretical consideration of vicariance biogeographers but in practice has been largely ignored by others. Previous approaches to assessing confidence in historical associations are examined here in relation to the difference between simple-event and cumulative probabilities and in relation …
Species Boundaries, Specialization, And The Radiation Of Sponge-Dwelling Alpheid Shrimp, J Duffy
Species Boundaries, Specialization, And The Radiation Of Sponge-Dwelling Alpheid Shrimp, J Duffy
VIMS Articles
Microevolutionary studies and natural history suggest that host-specialization has promoted the high diversity of tropical sponge-dwelling snapping shrimps (Decapoda, Alpheidae, Synalpheus). Yet the taxonomic difficulty of this genus has precluded rigorous tests of this hypothesis. S. rathbunae Coutiere is among the most abundant invertebrates inhabiting the framework of sponges and dead coral that forms the floor of Caribbean coral reefs. Even within a small area S. rathbunae exhibits the apparently wide variation in size, color, and morphology that has long frustrated efforts to identify and define species boundaries within this large (> 100 described species) genus. Here I show that …
Zostera Marina (Eelgrass) Growth And Survival Along A Gradient Of Nutrients And Turbidity In The Lower Chesapeake Bay, Ken Moore, Ha Neckles, R J. Orth
Zostera Marina (Eelgrass) Growth And Survival Along A Gradient Of Nutrients And Turbidity In The Lower Chesapeake Bay, Ken Moore, Ha Neckles, R J. Orth
VIMS Articles
Survival of transplanted Zostera marina L. (eelgrass), Z. marina growth, and environmental conditions were studied concurrently at a number of sites in a southwestern tributary of the Chesapeake Bay to elucidate the factors limiting macrophyte distribution in this region. Consistent differences in survival of the transplants were observed, with no long-term survival at any of the sites that were formerly vegetated with this species but that currently remain unvegetated. Therefore, the current distribution of Z. marina likely represents the extent of suitable environmental conditions in the region, and the lack of recovery into historically vegetated sites is not solely due …
Non-Structural Carbohydrate Reserves Of Eelgrass Zostera Marina, Mk Burke, Wc Dennison, Ka Moore
Non-Structural Carbohydrate Reserves Of Eelgrass Zostera Marina, Mk Burke, Wc Dennison, Ka Moore
VIMS Articles
The high minimum Light requirement of eelgrass Zostera marina L. suggests that this species has difficulty in maintaining a positive carbon balance except under high light conditions. The carbon balance of Z. marina can be studied by following seasonal changes in non-structural carbohydrate (NSC) reserves, however, little is known about the seasonal variation in NSC reserves in seagrasses or the influence of shading on NSC reserve content and distribution. Seasonal changes in eelgrass NSC reserves were measured in a shallow coastal lagoon, Chincoteague Bay, Maryland/Virginia, USA, near the southern edge of this species' distributional range. Concentrations of sugar varied seasonally …
Stratigraphic Consistency And The Shape Of Things, Mark E. Siddall
Stratigraphic Consistency And The Shape Of Things, Mark E. Siddall
VIMS Articles
No abstract provided.
The Magnitude And Persistence Of Soil No, N2o, Ch4, And Co, Fluxes From Burned Tropical Savanna In Brazil, M Poth, Iris C. Anderson, Et Al
The Magnitude And Persistence Of Soil No, N2o, Ch4, And Co, Fluxes From Burned Tropical Savanna In Brazil, M Poth, Iris C. Anderson, Et Al
VIMS Articles
Among all global ecosystems, tropical savannas are the most severely and extensively affected by anthropogenic burning. Frequency of fire in cerrado,a type of tropical savanna covering 25% of Brazil, is 2 to 4 years. In 1992 we measured soil fluxes of NO, N2O, CH4, and CO2 from cerrado sites that had been burned within the previous 2 days, 30 days, 1 year, and from a control site last burned in 1976. NO and N2O fluxes responded dramatically to fire with the highest fluxes observed from newly burned soils after addition of water. Emissions of N-trace gases after burning were of …
The Use Of Night-Vision Equipment To Observe Wildlife In Forested Wetlands, Kirk J. Havens, Walter I. Priest Iii, Ann Jennings
The Use Of Night-Vision Equipment To Observe Wildlife In Forested Wetlands, Kirk J. Havens, Walter I. Priest Iii, Ann Jennings
VIMS Articles
Urban forested wetlands and rural forested wetlands were studied to investigate the effectiveness of night-vision image intensifier equipment in the observation of medium-to-large animals and to investigate if surrounding landscape type influences wetland habitat value. Bats, cats, dogs, owls, deer, and humans were easily observed using the night-vision equipment. Differences in species use between the rural and urban forested wetland were observed. Light levels and noise levels were significantly higher (p
Introduction To The Proceedings Of The Blue Crab Recruitment Symposium, Ej Olmi, Rj Orth
Introduction To The Proceedings Of The Blue Crab Recruitment Symposium, Ej Olmi, Rj Orth
VIMS Articles
The blue crab, Callinectes sapidus Rathbun, is found in all major coastal habitats along the mid-Atlantic, South Atlantic and Gulf of Mexico coasts of the United States, including large embayments, barrier island-lagoonal systems, and coastal marsh, mangrove and seagrass systems. Ecologically important, blue crabs may control abundances of other estuarine benthic species (Hines et aI., 1990). The blue crab also supports valuable commercial and recreational fisheries from New Jersey to Texas; commercial landings of 249.3 million pounds of hard blue crabs in 1993 had a dockside value of 126.6 million dollars (NMFS, 1994). Blue crab stocks vary interannually within and …
Review Of Ecology And Fishery Of The Olympia Oyster, Ostrea Lurida With Annotated Bibliography, P Baker
Review Of Ecology And Fishery Of The Olympia Oyster, Ostrea Lurida With Annotated Bibliography, P Baker
VIMS Articles
The Olympia oyster, Ostrea lurida,is a small bivalve mollusk species native to the western United States and Canada. It was commercially important in the late 19th century, and was cultured in Washington State until a near-collapse of the industry in the 1950s. Since then it has made a minor commercial comeback, but has been largely superseded by the introduced Crassostrea gigas. Most significant literature dates from prior to the collapse of the industry in the 1950s, and much of this is comprised of state or federal agency reports, or similar obscure literature formats. This document is divided into 2 parts; …
Nitrification Potentials Of Benthic Macrofaunal Tubes And Burrow Walls: Effects Of Sediment Nh4+ And Animal Irrigation Behavior, Ms Mayer, L Schaffner, Wm Kemp
Nitrification Potentials Of Benthic Macrofaunal Tubes And Burrow Walls: Effects Of Sediment Nh4+ And Animal Irrigation Behavior, Ms Mayer, L Schaffner, Wm Kemp
VIMS Articles
We examined the natural variation of nitrification potentials (NPs) of surface sediments and macrofaunal tubes and burrow walls in relation to sediment NH4+ level, season, and macrofaunal species. NP (the ability of a unit of sediment to oxidize NH4+ when NH4+ and O-2 are not limiting) is an index of the abundance and activity of nitrifying bacteria which we measured in slurries with the chlorate block technique (nmol NO2--N produced g(-1) dry weight sediment h(-1)). The NP of the tubes of the polychaete Loimia medusa was positively related to sediment NH4+ (KCl-extractable) concentration at 3 sites where tubes were collected …
Seed Dispersal In A Marine Macrophyte - Implications For Colonization And Restoration, R J. Orth, Mark Luckenbach, Ken Moore
Seed Dispersal In A Marine Macrophyte - Implications For Colonization And Restoration, R J. Orth, Mark Luckenbach, Ken Moore
VIMS Articles
No abstract provided.
Aerobic And Anaerobic Degradation And Mineralization Of C-14 Chitin By Water Column And Sediment Inocula Of The York-River-Estuary, Virginia, Jn Boyer
VIMS Articles
Potential rates of chitin degradation (C(d)) and mineralization (C(m)) by estuarine water and sediment bacteria were measured as a function of inoculum source, temperature, and oxygen condition. In the water column inoculum, 88 to 93% of the particulate chitin was mineralized to CO2 with no apparent lag between degradation and mineralization. No measurable dissolved pool of radiolabel was found in the water column. For the sediment inocula, 70 to 90% of the chitin was degraded while only 55 to 65% was mineralized to CO2. C-14 label recoveries in the dissolved pool were 19 to 21% for sand, 17 to 24% …
Vertical Migration Of Blue Crab Callinectes Sapidus Megalopae: Implications For Transport In Estuaries, Ej Olmi
VIMS Articles
Following larval development in coastal waters, postlarvae (megalopae) of the blue crab Callinectes sapidus Rathbun enter inlets and, against the net seaward flow of estuarine waters, move upstream to juvenile habitats. Abundance and vertical distribution of blue crab megalopae in the York River, Virginia, USA, a subsetuary of Chesapeake Bay, was quanitified to examine the hypothesis that megalopae are not transported simply as passive particles, but display behaviors that augment their immigration. Megalopal abundance and depth distribution and environmental variables were measured at shallow (3 to 4 m) sites in 1988 and 1989 and at a deep (10 m) site …
Biological And Hydrodynamic Regulation Of The Microbial Food-Web In A Periodically Mixed Estuary, Pm Eldridge, Me Sieracki
Biological And Hydrodynamic Regulation Of The Microbial Food-Web In A Periodically Mixed Estuary, Pm Eldridge, Me Sieracki
VIMS Articles
Abundances of chroococcoid cyanobacteria and heterotrophic bacteria in surface waters of the York River subestuary covary with spring-neap tidally induced changes in the mixed-layer depth. Abundances of their principal grazers, heterotrophic protists, however, do not oscillate. A simulation model of this system using nonlinear, density-dependent functions has been developed to replicate cycles observed in the two bacterial abundances and simulate bacterial production and protistan grazing. A Jassby-Plan equation is used to determine growth rate from the mean mixed-layer light and empirically derived growth and a parameters. Changes in mixed-layer depth regulate light availability, thereby controlling cyanobacterial growth rates. The model …
Spatial And Temporal Bacterioplankton Dynamics During Destratification Of The James River Estuary, Virginia, Usa, Et Koepfler, Hi Kator, Rl Wetzel, Lw Haas
Spatial And Temporal Bacterioplankton Dynamics During Destratification Of The James River Estuary, Virginia, Usa, Et Koepfler, Hi Kator, Rl Wetzel, Lw Haas
VIMS Articles
Bacterioplankton abundance and production were examined over the course of a destratification event in the lower James River, Virginia, USA, Goals of the study were to determine if destratification would influence temporal patterns of bacterioplankton parameters and relationships between bacterioplankton and other biological and abiological parameters. Mean bacterial abundance grouped over stations did not change over the course of the study, and were characterized by much smaller coefficients of variation than all other planktonic constituents. However, bacterial production measured by H-3-thymidine (H-3-Tdr) incorporation decreased significantly from a stratified (324 mu g Cl-1 d(-1)) to a destratified (187 mu g Cl-1 …
Effects Of 2 Bloom-Forming Dinoflagellates, Prorocentrum-Minimum And Gyrodinium-Uncatenum, On The Growth And Survival Of The Eastern Oyster, Crassostrea-Virginica (Gmelin 1791), Mark Luckenbach, Kg Sellner, Se Shumway, K Greene
Effects Of 2 Bloom-Forming Dinoflagellates, Prorocentrum-Minimum And Gyrodinium-Uncatenum, On The Growth And Survival Of The Eastern Oyster, Crassostrea-Virginica (Gmelin 1791), Mark Luckenbach, Kg Sellner, Se Shumway, K Greene
VIMS Articles
Laboratory experiments were conducted to investigate the effects of the dinoflagellates Prorocentrum minimum and Gyrodinium uncatenum on the growth and survival of juvenile eastern oysters, Crassostrea virginica. In separate experiments lasting 30 d and 18 d for P. minimum and G. uncatenum, respectively, the dinoflagellates were offered to the oysters in both unialgal and mixed diets (with the diatom Thalassiosira weisflogii). Eight diets were used in each experiment: (i) the dinoflagellate at bloom density, (ii) the dinoflagellate at 33% bloom density, (iii) the dinoflagellate at 5% bloom density, (iv-vi) the diatom at the above densities, (vii) 50% dinoflagellate bloom density …
A Rapid Chromatographic Method For Recovery Of 15no2- And No3- Produced By Nitrification In Aqueous Samples, H Kator, Lj Morris, Rl Wetzel
A Rapid Chromatographic Method For Recovery Of 15no2- And No3- Produced By Nitrification In Aqueous Samples, H Kator, Lj Morris, Rl Wetzel
VIMS Articles
The sensitivity and comparative simplicity of N-15 stable isotopic tracer techniques has been used to quantify rates of nitrification in aquatic systems. However, the most commonly used method for recovery of inorganic oxidized nitrogen compounds from aqueous samples, which is based on liquid-liquid partitioning, is time consuming and contamination prone. We describe a solid-phase rapid chromatographic method for recovery of (NO2-)-N-15 and NO3- produced by nitrification in aqueous samples. Compared to liquid-liquid partitioning, the advantages are significantly reduced processing time and reduced potential for contamination. Typical results are presented for the tidal, freshwater reaches of the James River estuary.
Oligomer Composition And Oxygen Binding Of The Hemocyanin Of The Blue Crab Callinectes Sapidus, Cp Mangum, J Greaves, Js Rainer
Oligomer Composition And Oxygen Binding Of The Hemocyanin Of The Blue Crab Callinectes Sapidus, Cp Mangum, J Greaves, Js Rainer
VIMS Articles
In the blue crab, the ratio of hexamers to dodecamers of the O2 carrier hemocyanin varies in natural populations. Isolated dodecamers have a lower O2 affinity and greater cooperativity than isolated hexamers. The difference in O2 binding can also be resolved in native mixtures that differ in polymer composition. A high content of dodecamers in native mixtures is, in fact, correlated with the presence of an invariant polypeptide chain that is believed to link two hexamers to form dodecamers. On the other hand, the content of a variable chain that has been postulated to play a role in hexamer pairing …
Measurement Of Marine Picoplankton Cell-Size By Using A Cooled, Charge-Coupled Device Camera With Image-Analyzed Fluorescence Microscopy, Cl Viles, Me Sieracki
Measurement Of Marine Picoplankton Cell-Size By Using A Cooled, Charge-Coupled Device Camera With Image-Analyzed Fluorescence Microscopy, Cl Viles, Me Sieracki
VIMS Articles
Accurate measurement of the biomass and size distribution of picoplankton cells (0.2 to 2.0-mu-m) is paramount in characterizing their contribution to the oceanic food web and global biogeochemical cycling. Image-analyzed fluorescence microscopy, usually based on video camera technology, allows detailed measurements of individual cells to be taken. The application of an imaging system employing a cooled, slow-scan charge-coupled device (CCD) camera to automated counting and sizing of individual picoplankton cells from natural marine samples is described. A slow-scan CCD-based camera was compared to a video camera and was superior for detecting and sizing very small, dim particles such as fluorochrome-stained …
Unexplained Mortalities Of Hatchery-Reared, Juvenile Oysters, Crassostrea Virginica (Gmelin), Vm Bricelj, Se Ford, Fj Borrero, Fo Perkins, Et Al
Unexplained Mortalities Of Hatchery-Reared, Juvenile Oysters, Crassostrea Virginica (Gmelin), Vm Bricelj, Se Ford, Fj Borrero, Fo Perkins, Et Al
VIMS Articles
Survival. growth and pathology of juvenile oysters. Crassostrea virginica. in off-bottom culture at Oyster Bay and Fishers Island, New York, were monitored during the summer of 1991 to document and help explain the episodic mass mortalities of cultured seed oysters that have occurred in the northeastern USA over the past several years. Al Oyster Bay. where the more detailed study was conducted. 54 to 7So/o losses affected several 1991 cohorts at mean shell heights ranging from IS to 24 mm, within 3 to 6V, weeks of transfer from the hatchery to growout trays. Mortalities occurred in July and August, at …
Oligomer Composition And Oxygen Binding Of The Hemocyanin Of The Blue Crab Callinectes Sapidus, Cp Mangum, J Greaves, Js Ranier
Oligomer Composition And Oxygen Binding Of The Hemocyanin Of The Blue Crab Callinectes Sapidus, Cp Mangum, J Greaves, Js Ranier
VIMS Articles
In the blue crab, the ratio of hexamers to dodecamers of the O2 carrier hemocyanin varies in natural populations. Isolated dodecamers have a lower O2 affinity and greater cooperativity than isolated hexamers. The difference in O2 binding can also be resolved in native mixtures that differ in polymer composition. A high content of dodecamers in native mixtures is, in fact, correlated with the presence of an invariant polypeptide chain that is believed to link two hexamers to form dodecamers. On the other hand, the content of a variable chain that has been postulated to play a role in hexamer pairing …
Swimming Rate And Responses Of Larvae Of Three Mactrid Bivalves To Salinity Discontinuities, R Mann, Bm Campos, Mw Luckenbach
Swimming Rate And Responses Of Larvae Of Three Mactrid Bivalves To Salinity Discontinuities, R Mann, Bm Campos, Mw Luckenbach
VIMS Articles
Straight-hinge, umbo and pediveliger larvae of the mactrid bivalves Spisula solidissima, Mulinia lateralis and Rangia cuneata were exposed to intense salinity discontinuities of 0, 5, 10 and 15 parts per thousand in vertically oriented swimming chambers. Larvae concentrated in the region of highest gradient, i.e. at the salinity discontinuity, regardless of species, stage of development or larval brood. S. solidisima larvae, initially swimming at 30 parts per thousand salinity, crossed discontinuities of both 5 and 10 parts per thousand but not of 15 parts per thousand. M. lateralis larvae, initially swimming at 25 parts per thousand salinity, also crossed a …
Color Image-Analyzed Fluorescence Microscopy: A New Tool For Marine Microbial Ecology, Ml Sieracki, Cl Viles
Color Image-Analyzed Fluorescence Microscopy: A New Tool For Marine Microbial Ecology, Ml Sieracki, Cl Viles
VIMS Articles
BACTERIA, cyanobacteria, protozoa and small eukaryotic phytoplankton are now known to be funda- mental components of marine planktonic ecosystems (Azam et al., 1983; Sieburth, 1984). These organisms have high potential growth rates, are efficient convert- ers of material and energy, and usually constitute most of the plankton biomass (Davis et al., 1985; Fuhrman et al., 1989). Their different trophic levels are often closely coupled. These characteristics require that experimental and sampling designs for studying the microbial populations incorporate appropriate (i.e., small) temporal and spatial scales. The corollary to this is that large numbers of samples must be taken. If these …
Small-Scale Organism Distributions And Patterns Of Species Diversity: Evidence For Positive Interactions In An Estuarine Benthic Community, Linda C. Schaffner
Small-Scale Organism Distributions And Patterns Of Species Diversity: Evidence For Positive Interactions In An Estuarine Benthic Community, Linda C. Schaffner
VIMS Articles
No abstract provided.
Utilization Of Marsh And Seagrass Habitats By Early Stages Of Callinectes-Aapidus - A Latitudinal Perspective, R J. Orth, J Van Montfrans
Utilization Of Marsh And Seagrass Habitats By Early Stages Of Callinectes-Aapidus - A Latitudinal Perspective, R J. Orth, J Van Montfrans
VIMS Articles
Seagrass beds and marshes have been identified as important nurseries for the blue crab, Callinectes sapidus. This nursery paradigm is based on blue crab abundance data from trawl, seine and drop-net sampling that has revealed greater abundances in these habitats than in adjacent unvegetated areas. Recently, more quantitative and intensive sampling in seagrass beds and marshes over broad latitudinal scales, combined with manipulative experiments, indicate that the same habitat may vary in utilization on regional scales. Mechanisms accounting for enhanced abundances in these nursery habitats have not been elucidated from a latitudinal perspective. Regional comparisons of blue crab catch data …
Utilization Of A Seagrass Meadow And Tidal Marsh Creek By Blue Crabs Callinectes-Sapidus Ii. Spatial And Temporal Patterns Of Molting, Ch Ryer, J Van Montfrans, Rj Orth
Utilization Of A Seagrass Meadow And Tidal Marsh Creek By Blue Crabs Callinectes-Sapidus Ii. Spatial And Temporal Patterns Of Molting, Ch Ryer, J Van Montfrans, Rj Orth
VIMS Articles
Blue crabs were collected weekly from a lower Chesapeake Bay seagrass meadow and adjacent tidal marsh creek over 2 months (July-August 1987) and molt staged. Molting activity, determined from a total of I ,220 crabs, was greater in the grassbed than in the marsh creek, and greater for small crabs and females. The difference between the two habitats in molting activity decreased from the first to the second month of sampling, possibly in response to seasonal decline in seagrass biomass. The proportion of small (<70 mm) females in both habitats was greatest on full moons. There was a lunar rhythm of molting activity by large crabs (2:70 mm), with peak molting activity on fuIl moons. SmaIl crabs demonstrated a similar, but nonsignificant rhythm of molting. We suggest that blue crabs approaching ecdysis aggregate in seagrass meadows, taking advantage of the refuge from predation that this structurally complex habitat affords. Lunar rhythmicity of molting activity may further reduce predation mortality through a dilution effect.
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. …
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 …