MEPS 260:237-253 (2003)  -  doi:10.3354/meps260237

Effects of anthropogenic and natural disturbance on a recently settled continental shelf flatfish

Mark C. Sullivan1,*, Robert K. Cowen1, Kenneth W. Able2, Michael P. Fahay3

1Rosenstiel School of Marine and Atmospheric Science, Division of Marine Biology and Fisheries, University of Miami, 4600 Rickenbacker Causeway, Miami, Florida 33149, USA
2Marine Field Station, Institute of Marine and Coastal Sciences, Rutgers University, 800 c/o 132 Great Bay Boulevard, Tuckerton, New Jersey 08087, USA
3National Marine Fisheries Service, Northeast Fisheries Science Center, James J. Howard Marine Sciences Laboratory, 74 Magruder Road, Highlands, New Jersey 07732, USA

ABSTRACT: Concern over essential fish habitat characterization and conservation has directed attention toward the potential impact of mobile fishing gear on benthic ecosystems. However, previous findings do not necessarily extend to all environments, life stages, and/or gear types. The juvenile stage of benthic marine fishes is one such life stage that may be sensitive to disturbance. We examined the impact of commercial scallop dredge gear on a recently settled, continental shelf fish within the context of a sand sediment, storm-dominated system, the New York Bight. From June 1999 to July 2000, experimental manipulations with spatially replicated control-impact effects were used to investigate the immediate and longer-term consequences of a dredging event on young-of-the-year (YOY) yellowtail flounder Limanda ferruginea and its benthic nursery habitat. Contrary to expectation, L. ferruginea abundance did not decrease significantly immediately after dredging. Rather, at high-density sites, continued recruitment generated increases of smaller individuals across treatments. A significant decrease of older YOY L. ferruginea and available benthic prey was observed 3 mo later following a series of major natural perturbations (Hurricanes Dennis, Floyd, and Gert). Using concomitant buoy data, we also examined the physical regime of the region as it relates to important benthic settlement windows. Increased levels of natural disturbance during the fall and winter months appeared to play a critical role in shaping inner-mid-shelf seafloor architecture, effectively obscuring any longer term dredge-related signals. The results, overall, tend to highlight the vulnerability of New York Bight shelf habitats to multiple forms of disturbance.


KEY WORDS: Dredging · Juvenile fish · Limanda ferruginea · Disturbance · New York Bight · Nursery habitat · Storms · Submersible


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