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- Chesapeake Bay (8)
- Otolith (6)
- Otoliths (5)
- Atlantic croaker (4)
- Blue crab (4)
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- Age determination (3)
- Lipofuscin (3)
- Otolith chemistry (3)
- Age pigment (2)
- Atlantic Ocean (2)
- Decapoda (Crustacea) (2)
- Larval ingress (2)
- Micropogonias undulatus (2)
- Mid-Atlantic bight (2)
- ANN (1)
- Age and growth (1)
- Age growth (1)
- Alosa sapidissima (1)
- Antarctic circumpolar current (1)
- Antarctica (1)
- Aquaculture ponds (1)
- Aquatic pathogens (1)
- Assessment method (1)
- Atlantic Ocean (Southwest) (1)
- Attached bacteria (1)
- Biochemical composition (1)
- Biological hotspot (1)
- Bomb radiocarbon (1)
- C-14 (1)
- CCAMLR (1)
Articles 1 - 26 of 26
Full-Text Articles in Animal Sciences
Imaging Technologies Build Capacity And Accessibility In Phytoplankton Species Identification Expertise For Research And Monitoring: Lessons Learned During The Covid-19 Pandemic, Sophie Clayton, Leah Gibala-Smith, Kathryn Mogatas, Chanel Flores-Vargas, Kayla Marciniak, Maci Wigginton, Margaret R. Mulholland
Imaging Technologies Build Capacity And Accessibility In Phytoplankton Species Identification Expertise For Research And Monitoring: Lessons Learned During The Covid-19 Pandemic, Sophie Clayton, Leah Gibala-Smith, Kathryn Mogatas, Chanel Flores-Vargas, Kayla Marciniak, Maci Wigginton, Margaret R. Mulholland
OES Faculty Publications
As primary producers, phytoplankton play an integral role in global biogeochemical cycles through their production of oxygen and fixation of carbon. They also provide significant ecosystem services, by supporting secondary production and fisheries. Phytoplankton biomass and diversity have been identified by the Global Ocean Observing System (GOOS) as Essential Ocean Variables (EOVs), properties that need to be monitored to better understand and predict the ocean system. Phytoplankton identification and enumeration relies on the skills and expertise of highly trained taxonomic analysts. The training of new taxonomic analysts is intensive and requires months to years of supervised training before an analyst …
A Subsurface Eddy Associated With A Submarine Canyon Increases Availability And Delivery Of Simulated Antarctic Krill To Penguin Foraging Regions, K. Hudson, M. J. Oliver, J. Kohut, Michael S. Dinniman, John M. Klinck, M. A. Cimino, K. S. Bernard, H. Statscewich, W. Fraser
A Subsurface Eddy Associated With A Submarine Canyon Increases Availability And Delivery Of Simulated Antarctic Krill To Penguin Foraging Regions, K. Hudson, M. J. Oliver, J. Kohut, Michael S. Dinniman, John M. Klinck, M. A. Cimino, K. S. Bernard, H. Statscewich, W. Fraser
OES Faculty Publications
The distribution of marine zooplankton depends on both ocean currents and swimming behavior. Many zooplankton perform diel vertical migration (DVM) between the surface and subsurface, which can have different current regimes. If concentration mechanisms, such as fronts or eddies, are present in the subsurface, they may impact zooplankton near-surface distributions when they migrate to near-surface waters. A subsurface, retentive eddy within Palmer Deep Canyon (PDC), a submarine canyon along the West Antarctic Peninsula (WAP), retains diurnal vertically migrating zooplankton in previous model simulations. Here, we tested the hypothesis that the presence of the PDC and its associated subsurface eddy increases …
Bomb Radiocarbon Age Validation For The Long-Lived, Unexploited Arctic Fish Species Coregonus Clupeaformis, John M. Casselman, Cynthia M. Jones, Steven E. Campana
Bomb Radiocarbon Age Validation For The Long-Lived, Unexploited Arctic Fish Species Coregonus Clupeaformis, John M. Casselman, Cynthia M. Jones, Steven E. Campana
OES Faculty Publications
The growth rates of freshwater fish in the Arctic would be expected to be very low, but some previous studies of lake whitefish (Coregonus clupeaformis) have reported relatively rapid growth and longevity estimates of less than 15 years. We used bomb radiocarbon chronologies to validate an ageing method based on otolith sections for lake whitefish in both an unexploited Arctic lake (MacAlpine Lake; longevity 50 years) and a lightly exploited temperate population (Lake Simcoe; longevity 49 years). Our results confirm previous suggestions that other ageing methods can seriously underestimate lake whitefish age after ~5–8 years. A Chapman–Robson estimate …
Frontiers In Otolith Chemistry: Insights, Advances And Applications, B. D. Walther, K. E. Limburg, C. M. Jones, J. J. Schaffler
Frontiers In Otolith Chemistry: Insights, Advances And Applications, B. D. Walther, K. E. Limburg, C. M. Jones, J. J. Schaffler
OES Faculty Publications
The rapid proliferation of publications employing chemical assays of fish hard parts, and otoliths in particular, has led to many novel insights into the migration patterns, life history strategies and mixed stock dynamics of fishes across the globe (Campana et al., 2000; Elsdon et al., 2008; Walther & Limburg, 2012). These insights include uncovering diverse migratory strategies within species and populations (Kerr et al., 2009; Hogan et al., 2014; Schoen et al., 2016), quantifying rates of mixing among stocks across management boundaries (Rooker et al., 2008; Walther & Thorrold, 2010) and estimating the relative …
Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler
Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler
OES Faculty Publications
Classification method performance was evaluated using otolith chemistry of juvenile Atlantic menhaden Brevoortia tyrannus when assumptions of data normality were met and were violated. Four methods were tested [linear discriminant function analysis (LDFA), quadratic discriminant function analysis (QDFA), random forest (RF) and artificial neural networks (ANN)] using computer simulation to determine their performance when variable-group means ranged from small to large and their performance under conditions of typical skewness to double the amount of skewness typically observed. Using the kappa index, the parametric methods performed best after applying appropriate data transformation, gaining 2% better performance with LDFA performing slightly better …
The Contribution Of Marine Aggregate-Associated Bacteria To The Accumulation Of Pathogenic Bacteria In Oysters: An Agent-Based Model, Andrew M. Kramer, J. Evan Ward, Fred C. Dobbs, Melissa L. Pierce
The Contribution Of Marine Aggregate-Associated Bacteria To The Accumulation Of Pathogenic Bacteria In Oysters: An Agent-Based Model, Andrew M. Kramer, J. Evan Ward, Fred C. Dobbs, Melissa L. Pierce
OES Faculty Publications
Bivalves process large volumes of water, leading to their accumulation of bacteria, including potential human pathogens (e.g., vibrios). These bacteria are captured at low efficiencies when freely suspended in the water column, but they also attach to marine aggregates, which are captured with near 100% efficiency. For this reason, and because they are often enriched with heterotrophic bacteria, marine aggregates have been hypothesized to function as important transporters of bacteria into bivalves. The relative contribution of aggregates and unattached bacteria to the accumulation of these cells, however, is unknown. We developed an agent-based model to simulate accumulation of vibrio-type bacteria …
A Highly Sensitive Underwater Video System For Use In Turbid Aquaculture Ponds, Chin-Chang Hung, Shih-Chieh Tsao, Kuo-Hao Huang, Hsu-Kunag Chang, Fred C. Dobbs
A Highly Sensitive Underwater Video System For Use In Turbid Aquaculture Ponds, Chin-Chang Hung, Shih-Chieh Tsao, Kuo-Hao Huang, Hsu-Kunag Chang, Fred C. Dobbs
OES Faculty Publications
The turbid, low-light waters characteristic of aquaculture ponds have made it difficult or impossible for previous video cameras to provide clear imagery of the ponds' benthic habitat. We developed a highly sensitive, underwater video system (UVS) for this particular application and tested it in shrimp ponds having turbidities typical of those in southern Taiwan. The system's high-quality video stream and images, together with its camera capacity (up to nine cameras), permit in situ observations of shrimp feeding behavior, shrimp size and internal anatomy, and organic matter residues on pond sediments. The UVS can operate continuously and be focused remotely, a …
Fish Species Distribution In Seagrass Habitats Of Chesapeake Bay Are Structured By Abiotic And Biotic Factors, Jason J. Schaffler, Jacques Van Montfrans, Cynthia M. Jones, Robert J. Orth
Fish Species Distribution In Seagrass Habitats Of Chesapeake Bay Are Structured By Abiotic And Biotic Factors, Jason J. Schaffler, Jacques Van Montfrans, Cynthia M. Jones, Robert J. Orth
OES Faculty Publications
Seagrass habitats have long been known to serve as nursery habitats for juvenile fish by providing refuges from predation and areas of high forage abundance. However, comparatively less is known about other factors structuring fish communities that make extensive use of seagrass as nursery habitat. We examined both physical and biological factors that may structure the juvenile seagrass-associated fish communities across a synoptic-scale multiyear study in lower Chesapeake Bay. Across 3years of sampling, we collected 21,153 fish from 31 species. Silver Perch Bairdiella chrysoura made up over 86% of all individuals collected. Nine additional species made up at least 1% …
Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones
Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones
OES Faculty Publications
Life history scans of fish otoliths are bringing new insight into the structure, connectivity, and movement of fish populations. Data obtained from such scans, however, possess in-herent limitations that have not yet been fully addressed or understood. For example, several investigators have noted delays in otolith elemental uptake that do not appear to reflect habitat exposure. We hypothesized that the 3-dimensional structure of otoliths may produce sampling artifacts in the results obtained from laser ablation scans. To test this hypothesis, we sampled sagittal otoliths from juvenile Atlantic croaker Micropogonias undulatus with laser ablation inductively coupled plasma mass spectrometry to obtain …
Spatial Variation In Otolith Chemistry Of Atlantic Croaker Larvae In The Mid-Atlantic Bight, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones
Spatial Variation In Otolith Chemistry Of Atlantic Croaker Larvae In The Mid-Atlantic Bight, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones
OES Faculty Publications
Larval Atlantic croaker Micropogonias undulatus (1 to 7 mm in standard length) were collected on the east coast of the United States from North Carolina to Delaware during 2000. We defined 3 water-mass boundaries for potential groups of spawning Atlantic croaker using temperature and salinity measured at each sampling station. We tested the hypothesis that distinct otolith chemistries existed among 3 groups of larval Atlantic croaker collected from these water masses using solution-based inductively coupled plasma-mass spectrometry. Multivariate analysis of variance indicated that otolith chemistry differed significantly among water masses. Using a quadratic discriminant function, we were able to correctly …
Patterns Of Larval Atlantic Croaker Ingress Into Chesapeake Bay, Usa, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones
Patterns Of Larval Atlantic Croaker Ingress Into Chesapeake Bay, Usa, Jason J. Schaffler, Christian S. Reiss, Cynthia M. Jones
OES Faculty Publications
We compared ingress patterns of Atlantic croaker Micropogonias undulatus larvae into Chesapeake Bay, USA, with published ingress patterns through barrier island inlets, the accepted model for larval fish ingress. This model asserts that larvae ingress on night flood tides at the flooddominated side of the inlet and at all depths. At the Chesapeake Bay mouth and in the adjacent coastal waters, we compared the distribution of abundance, size, age, and growth rates of croaker prior to ingress, In contrast to the barrier island inlet model, croaker larvae were more abundant at depth than closer to the surface regardless of location. …
The Use Of Extractable Lipofuscin For Age Determination Of Crustaceans: Reply To Sheehy (2008), H. Rodger Harvey, David H. Secor, Se-Jong Ju
The Use Of Extractable Lipofuscin For Age Determination Of Crustaceans: Reply To Sheehy (2008), H. Rodger Harvey, David H. Secor, Se-Jong Ju
OES Faculty Publications
The heterogeneous mixture of metabolic by-products termed lipofuscin (LF) or age pigments has long been known to accumulate in post mitotic cells with increasing age. In crustaceans several approaches have been developed over the years to track LF accumulation and provide a proxy for chronological age. Histological approaches have been traditionally used for LF determination of crustaceans (e.g. Sheehy et al. 1994, Mar Biol 121:237-245), but over the last decade extraction approaches for neural tissues have been introduced (Ju et al. 1999, Mar Ecol Prog Ser 185:171-179) and tested (Ju et al. 2001, Mar Ecol Prog Ser 224:197-205; 2003, Fish …
Otolith Chemistry Reflects Frontal Systems In The Antarctic Circumpolar Current, J. R. Ashford, A. I. Arkhipkin, C. M. Jones
Otolith Chemistry Reflects Frontal Systems In The Antarctic Circumpolar Current, J. R. Ashford, A. I. Arkhipkin, C. M. Jones
OES Faculty Publications
Pronounced environmental trends across fronts suggest that the otolith chemistry of oceanic fish can resolve zones on either side, promoting application to population questions at similar spatial scales. Trace and minor elements laid down immediately prior to capture - along the edges of otoliths from Patagonian toothfish Dissostichus eleginoides - discriminated frontal zones in the Antarctic Circumpolar Current in the Southwestern Atlantic Ocean. Mean values differentiated sampling areas by up to 2.6 standard deviations, suggesting: (1) otolith Mg/Ca enrichment related to fish activity around the Burdwood Bank; (2) Mn/Ca enrichment associated with South America; (3) Sr/Ca linked to the presence …
Substituting Otoliths For Chemical Analyses: Does Sagitta = Lapillus?, Nathan G. Smith, Cynthia M. Jones
Substituting Otoliths For Chemical Analyses: Does Sagitta = Lapillus?, Nathan G. Smith, Cynthia M. Jones
OES Faculty Publications
Chemical analysis of fish otoliths has become an important technique in fisheries science with widespread applications. Most research up to this point has focused predominantly on sagittal otoliths, but the underlying assumptions may also apply to lapilli. The goal of this study was to determine whether lapilli and sagittae have the same otolith chemistry and whether one can be substituted for the other for solution-based chemical analysis in wild-captured fish. We compared the stable isotope chemistry (δ13C and δ18O) of paired sagittae and lapilli of juvenile spotted seatrout Cynoscion nebulosus collected from Chesapeake Bay seagrass beds in 2002. …
Biophysical Mechanisms Of Larval Fish Ingress Into Chesapeake Bay, Jonathan A. Hare, Simon Thorrold, Harvey Walsh, Christian Reiss, Arnoldo Valle-Levinson, Cynthia Jones
Biophysical Mechanisms Of Larval Fish Ingress Into Chesapeake Bay, Jonathan A. Hare, Simon Thorrold, Harvey Walsh, Christian Reiss, Arnoldo Valle-Levinson, Cynthia Jones
OES Faculty Publications
Selective tidal stream transport is hypothesized as a dominant mechanism by which larvae of marine animals move through estuarine openings. For larvae moving from the shelf to estuarine habitats, selective tidal stream transport proposes that larvae are higher in the water column during flood tide and lower in the water column during ebb tide. Although a number of studies conclude that selective tidal stream transport is the mechanism responsible for larval ingress, few studies consider alternative mechanisms or consider passive explanations for tidal patterns in larval distributions. We examined the biophysical mechanisms responsible for larval ingress into Chesapeake Bay using …
Age And Growth Of Scotia Sea Icefish, Chaenocephalus Aceratus, From The South Shetland Islands, M. La Mesa, J. Ashford, E. Larson, M. Vacchi
Age And Growth Of Scotia Sea Icefish, Chaenocephalus Aceratus, From The South Shetland Islands, M. La Mesa, J. Ashford, E. Larson, M. Vacchi
OES Faculty Publications
Samples of Chaenocephalus aceratus (Lönnberg) were collected during a trawl survey carried out around the South Shetland Islands in January–February 2002. Fish were caught by commercial bottom trawl fishing down to 500 m depth, using a stratified randomized sampling design. As observed in other recent surveys within the same area, C. aceratus represented one of the predominant species. Overall, 357 specimens ranging from 13 and 67 cm (TL) were selected for the present study. Ages were estimated by counting annuli present in the sagittal otoliths, exposed by grinding and polishing along their sagittal plane. To estimate the precision of age …
Demographic Assessment Of The Blue Crab (Callinectes Sapidus) In Chesapeake Bay Using Extractable Lipofuscins As Age Markers, Se-Jong Ju, David H. Secor, H. Rodger Harvey
Demographic Assessment Of The Blue Crab (Callinectes Sapidus) In Chesapeake Bay Using Extractable Lipofuscins As Age Markers, Se-Jong Ju, David H. Secor, H. Rodger Harvey
OES Faculty Publications
The blue crab (Callinectes sapidus) plays an important economic and ecological role in estuaries and coastal habitats from the Gulf of Mexico to the east coast of North America, but demographic assessments are limited by length-based methods. We applied an alternative aging method using biochemical measures of metabolic byproducts (lipofuscins) sequestered in the neural tissue of eyestalks to examine population age structure. From Chesapeake Bay, subsamples of animals collected from the 1998-99 (n-769) and 1999-2000 (n=367) winter dredge surveys were collected and lipofuscin was measured. Modal analysis of the lipofuscin index provided separation into three modes, whereas carapace-width …
Growth Rate Variability And Lipofuscin Accumulation Rates In The Blue Crab Callinectes Sapidus, Se-Jong Ju, David H. Secor, H. Rodger Harvey
Growth Rate Variability And Lipofuscin Accumulation Rates In The Blue Crab Callinectes Sapidus, Se-Jong Ju, David H. Secor, H. Rodger Harvey
OES Faculty Publications
To better understand growth and age-pigment (lipofuscin) accumulation rates of the blue crab Callinectes sapidus under natural conditions, juveniles (33 to 94 mm carapace width) were reared in outdoor ponds for over 1 yr. Growth rates, measured by carapace width, during summer and fall exceeded all those reported in the literature; the initial carapace width of 59 ± 14 mm (mean ± SD) increased to 164 ± 15 mm within a 3 mo period. No growth occurred during winter months (November to April) at low water temperatures. Growth rates of crabs in ponds were substantially higher (von Bertalanffy growth parameter …
Radiocarbon From Nuclear Testing Applied To Age Validation Of Black Drum, Pogonias Cromis, Steven E. Campana, Cynthia M. Jones
Radiocarbon From Nuclear Testing Applied To Age Validation Of Black Drum, Pogonias Cromis, Steven E. Campana, Cynthia M. Jones
OES Faculty Publications
Radiocarbon ((14)C) in the world's oceans increased sharply between 1950 and 1970 as a result of the atmospheric testing of nuclear weapons. Through comparison with the (14)C time series reconstructed from atmospheric measurements and marine carbonates, Kalish, in 1993, used the (14)C concentration measured in fish otolith cores as a means of confirming the annulus-based age estimates for some South Pacific fish species. Here we report the pre-and postbomb (14)C chronology of North Atlantic adult black drum (Pogonias cronis), assumed to be between 15 and 42 yr of age on the basis of otolith annulus counts. According to …
Trace Element Signatures In Otoliths Record Natal River Of Juvenile American Shad (Alosa Sapidissima), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana, James W. Mclaren, Joseph W. H. Lam
Trace Element Signatures In Otoliths Record Natal River Of Juvenile American Shad (Alosa Sapidissima), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana, James W. Mclaren, Joseph W. H. Lam
OES Faculty Publications
The elemental composition of fish otoliths may represent a permanent record of the environmental conditions an individual has experienced as trace elements, incorporated into the growing surface of the otolith, reflect the physical and chemical characteristics of the ambient water. We tested the utility of trace element signatures in otoliths as natural tags of the river of origin of juvenile American shad (Alosa sapidissima) collected from the Connecticut, Hudson and Delaware Rivers in August and October 1994. Four elements (K, Mn, Sr, and Ba) showed significant variability among sites within rivers in August, although only Mg showed a …
Yield-Per-Recruit Analysis And Management Strategies For Atlantic Croaker, Micropogonias Undulatus, In The Middle Atlantic Bight, Luiz R. Barbieri, Mark E. Chittenden, Cynthia M. Jones
Yield-Per-Recruit Analysis And Management Strategies For Atlantic Croaker, Micropogonias Undulatus, In The Middle Atlantic Bight, Luiz R. Barbieri, Mark E. Chittenden, Cynthia M. Jones
OES Faculty Publications
The effect of different fishing mortality (F) and natural mortality (M), and age at first capture (t(c)) on yield-per-recruit of Atlantic croaker, Micropogonias undulatus, in the lower Chesapeake Bay and North Carolina were evaluated with the Beverton-Holt model. Independent of the level of M (0.20-0.35) or F (0.01-2.0) used in simulations, yield-per-recruit values for Chesapeake Bay were consistently higher at t((c)) = 1 and decreased continuously with increases in t(c) (2-5). Although maximum yield-per-recruit always occurred at the maximum level off (F=2.0), marginal increases in yield beyond F = 0.50-0.75 were negligible. Current F (F(CUR)) is estimated to be …
Age And Growth Of Larval And Juvenile Atlantic Croaker, Micropogonias Undulatus, From The Middle Atlantic Bight And Estuarine Waters Of Virginia, Stephen W. Nixon, Cynthia M. Jones
Age And Growth Of Larval And Juvenile Atlantic Croaker, Micropogonias Undulatus, From The Middle Atlantic Bight And Estuarine Waters Of Virginia, Stephen W. Nixon, Cynthia M. Jones
OES Faculty Publications
Sagittal otoliths were used to determine age and growth of 605 larval and juvenile Atlantic croaker, Micropogonias undulatus, collected in the Middle Atlantic Bight and estuarine waters of Virginia. This study is the first to use age-based analysis for young Atlantic croaker collected in this region. A Laird-Gompertz model (r2=0.95) was used to describe the growth of Atlantic croaker up to 65 mm standard length (SL) and 142 days (t): SL((t)) = 2.657 exp (4.656 [1-exp (-0.0081t)]); where SL((t)) = standard length at day t. Spatial and temporal patterns in the size and age of Atlantic croaker showed a …
Response Of Otolith Microchemistry To Environmental Variations Experienced By Larval And Juvenile Atlantic Croaker (Micropogonias Undulatus), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana
Response Of Otolith Microchemistry To Environmental Variations Experienced By Larval And Juvenile Atlantic Croaker (Micropogonias Undulatus), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana
OES Faculty Publications
Minor and trace elements incorporated into otoliths during growth may permanently record environmental conditions experienced by fishes. To determine the validity of this approach, we used laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) to assay sectioned otoliths from juvenile Atlantic croaker (Micropogonias undulatus) collected from each of three sites in the Neuse River, North Carolina, and the Elizabeth River, Virginia. Elemental concentrations at the center of the otoliths did not differ between locations, although both Mg : Ca and Ba : Ca were significantly higher at the edge of otoliths from the Neuse River than from the …
Age, Growth, And Mortality Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Region, With A Discussion Of Apparent Geographic Changes In Population Dynamics, Luiz R. Barbieri, Mark E. Chittenden Jr., Cynthia M. Jones
Age, Growth, And Mortality Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Region, With A Discussion Of Apparent Geographic Changes In Population Dynamics, Luiz R. Barbieri, Mark E. Chittenden Jr., Cynthia M. Jones
OES Faculty Publications
Atlantic croaker, Micropogonias undulatus, collected from commercial catches in Chesapeake Bay and in Virginia and North Carolina coastal waters during 1988-1991 (n=1,967) were aged from transverse otolith sections. Ages 1-8 were recorded, but eight-year-old fish were rare. Marginal increment analysis showed that for ages 1-7, annuli are formed once a year during the period April-May. Otolith age readings were precise: >99% agreement within and between readers. Observed lengths-at-age were highly variable and growth rate decreased after the first year. Despite the high variability in sizes-at-age, observed lengths for ages 1-7 fit the von Bertalanffy growth model (r2=0.99; n=753) well. …
Estimates Of Spawning Stock Size Of Blue Crab, Callinectes Sapidus, In Chesapeake Bay, 1986-1987, Cynthia M. Jones, John R. Mcconaugha, Patrick J. Geer, Michael H. Prager
Estimates Of Spawning Stock Size Of Blue Crab, Callinectes Sapidus, In Chesapeake Bay, 1986-1987, Cynthia M. Jones, John R. Mcconaugha, Patrick J. Geer, Michael H. Prager
OES Faculty Publications
The 1986 spawning stock exhibited a single abundance peak, increasing from 1.0×105 individuals in early July to 9.3×106 in late July, maintaining high levels throughout the summer, and declining in the fall to 7.4×105 individuals. The 1987 spawning stock showed 2 peaks of abundance. The population reached the lesser peak, 1.0×106 individuals, in late July; the greater peak, 1.5×106, in late August. By late September, the population had declined to 6.5×105 individuals. The peak abundance of the 1987 female spawning stock was only 16% as great as the peak abundance in 1986; the 1987 spawning stock size in 1986. Variability …
Fecundity Of Blue Crab, Callinectes Sapidus, In Chesapeake Bay: Biological, Statistical And Management Considerations, Michael H. Prager, John R. Mcconaugha, Cynthia M. Jones, Patrick J. Geer
Fecundity Of Blue Crab, Callinectes Sapidus, In Chesapeake Bay: Biological, Statistical And Management Considerations, Michael H. Prager, John R. Mcconaugha, Cynthia M. Jones, Patrick J. Geer
OES Faculty Publications
Ovigerous blue crabs were collected from the mouth of Chesapeake Bay during the 1986 and 1987 spawning seasons. Mean carapace width was 14.7 cm; mean fecundity was 3.2×106 eggs. Fecundity was significantly related to carapace width, and did not vary significantly with developmental stage of the eggs. Mean fecundities were 2.6×106 eggs in 1986, and 4.0×106 eggs in 1987. An additive model with year and size effects described the observed fecundities reasonably well, was compact, and was easier to interpret than a multiplicative model. To fit a more general model without year effects, the authors took the mean of 1986 …