Recent paper abstracts
Gallagher, B.K., L.A. Hice, A.E. McElroy, R.M. Cerrato, M.G. Frisk (In Press). Factors Influencing Daily Growth in Young-of-the-Year Winter Flounder along an Urban Gradient Revealed Using Hierarchical Linear Models. Marine and Coastal Fisheries.
timing is required to unravel the complex behavior of Winter Flounder.
Abstract: In contrast to freshwater fish it is presumed that marine fish are unlikely to spawn with close relatives due to the dilution effect of large breeding populations and their propensity for movement and reproductive mixing. Inbreeding is therefore not typically a focal concern of marine fish management. We measured the effective number of breeders in 6 New York estuaries for winter flounder (Pseudopleuronectes americanus), a formerly abundant fish, using 11 microsatellite markers (6-56 alleles per locus). The effective number of breeders for 1-2 years was remarkably small, with point estimates ranging from 65-289 individuals. Excess homozygosity was detected at 10 loci in all bays (F-IS = 0.169-0.283) and individuals exhibited high average internal relatedness (IR; mean = 0.226). These both indicate that inbreeding is very common in all bays, after testing for and ruling out alternative explanations such as technical and sampling artifacts. This study demonstrates that even historically common marine fish can be prone to inbreeding, a factor that should be considered in fisheries management and conservation plans.
Collier, J.L., S.P. Fitzgerald, L.A. Hice, M.G. Frisk, and A.E. McElroy (2014). A New PCR-based Method Shows that Blue Crabs (Callinectes sapidus) Prey on Winter Flounder (Pseudopleuronectes americanus Walbaum)). PLoS ONE.
Abstract: Winter flounder (Pseudopleuronectes americanus) once supported robust commercial and recreational fisheries in the New York (USA) region, but since the 1990s populations have been in decline. Available data show that settlement of young-of-the-year winter flounder has not declined as sharply as adult abundance, suggesting that juveniles are experiencing higher mortality following settlement. The recent increase of blue crab (Callinectes sapidus) abundance in the New York region raises the possibility that new sources of predation may be contributing to juvenile winter flounder mortality. To investigate this possibility we developed and validated a method to specifically detect winter flounder mitochondrial control region DNA sequences in the gut contents of blue crabs. A survey of 55 crabs collected from Shinnecock Bay (along the south shore of Long Island, New York) in July, August, and September of 2011 showed that 12 of 42 blue crabs (28.6%) from which PCR-amplifiable DNA was recovered had consumed winter flounder in the wild, empirically supporting the trophic link between these species that has been widely speculated to exist. This technique overcomes difficulties with visual identification of the often unrecognizable gut contents of decapod crustaceans, and modifications of this approach offer valuable tools to more broadly address their feeding habits on a wide variety of species.
Abstract: We implanted individually coded acoustic transmitters into 40 adult winter flounder Pseudopleuronectes americanus (mean total length = 320 mm; range = 240–423 mm) and monitored them by use of passive acoustic telemetry from September 2007 to April 2009 to classify spatial and temporal movement patterns and quantify residency in Shinnecock Bay, eastern Long Island, New York. Overall, 94,250 valid detections were received. Winter flounder remained inshore, and 89% of the total detections occurred between May and October when bottom water temperature exceeded 15◦C. Residency in Shinnecock Bay was dependent on time of release and varied greatly from a few weeks to more than 6 months; total presence (number of days on which individual fish were detected within the bay) averaged 22.0 d (range = 1–132 d). Tracked winter flounder were classified as exhibiting three movement patterns: (1) inner bay movements (short term versus long term), (2) dispersal to offshore waters, and (3) connectivity to other inshore areas. The first two patterns were consistent with historical notions of spatially overlapping resident and migratory individuals, whereas fish that displayed the third pattern may have exhibited a larger home range. These results provide insight into winter flounder movements, residency, and stock structure in a coastal bay of Long Island and provide important information for management. The interaction of exploitation and divergent migration behaviors may be a factor contributing to the winter flounder’s decline in Long Island bays; however, much more work will be required to obtain a full understanding of the spatial behavior and stock structure of this species.
Abstract: Developing models in support of ecosystem-based management requires knowledge of trophic dynamics of ecologically important species. A paucity of data on these dynamics for Long Island fi nfi sh is hindering development of ecosystem models required by recent legislation. In this study, we analyzed stomach contents of common fishes collected from Port Jefferson Harbor, Great South Bay, and Shinnecock Bay between May and October of 2007 and 2008. General diet composition was described by percent by number (%N), percent by weight (%W) and percent frequency of occurrence (%O) for seven species: Paralichthys dentatus (Summer Flounder), young-of-the-year (YOY) Pomatomus saltatrix(Bluefi sh), Prionotus evolans (Striped Searobin), Stenotomus chrysops (Scup), Scophthalmus aquosus (Windowpane Flounder), Raja eglanteria (Clearnose Skate), and Morone saxatilis (Striped Bass). Temporal diet composition was estimated for the consistently abundant YOY Bluefi sh, Summer Flounder, and Scup, where most nseason > 25. Subsampling of large catches of YOY Bluefi sh and Scup led to investigation of diet composition by cluster sampling. Important prey included Crangon sp. (sand shrimp), Cancer irroratus (Rock Crab), and forage fi shes.Pseudopleuronectes americanus (Winter Flounder), once a common prey item in stomachs of piscivorous Long Island fi shes, contributed ≤ 6.7 %O and ≤ 1.6 %W to the diets of Summer Flounder, Striped Searobin, Striped Bass, and YOY Bluefi sh. These changes may be due to shifts in the abundance of prey items or changes in spatial overlap of predator and prey.