MEPS 327:267-277 (2006)  -  doi:10.3354/meps327267

Fate of fish production in a seasonally flooded saltmarsh

Philip W. Stevens1,2,3,*, Clay L. Montague1, Kenneth J. Sulak2

1Department of Environmental Engineering Sciences, University of Florida, PO Box 116450, Gainesville, Florida 32611-6450, USA
2Center for Aquatic Resource Studies, US Geological Survey, 7920 NW 71 St, Gainesville, Florida 32653, USA
3Present address: Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 1481 Market Circle, Port Charlotte, Florida 33953, USA

ABSTRACT: Although saltmarshes are thought to enhance the productivity of open estuarine waters, the mechanism by which energy transfer occurs has been debated for decades. One possible mechanism is the transfer of saltmarsh production to estuarine waters by vagile fishes and invertebrates. Monthly estimates of fish standing stock, net fish ingress, and predation were used to develop a biomass budget to estimate annual production of fishes and the relative yield to predatory fish, birds, and direct migration to the estuary. Annual production of saltmarsh fishes was estimated to be 31.0 g m–2 saltmarsh, which falls within the range of previously reported values for estuarine fish communities. The relative yields were 12 to 20% to piscivorous fishes, 8 to 13% to piscivorous birds, and 18 to 29% to export. Annual export of fish biomass was 5.6 g fish m–2 saltmarsh, representing about 1 to 2% of saltmarsh primary production. Saltmarsh fishes convert marsh production to high-quality vagile biomass (fishes concentrate energy, protein, and nutrients as body mass) and move this readily useable production to the estuary, providing an efficient link between saltmarshes and estuarine predators.


KEY WORDS: Saltmarsh impoundment · Outwelling hypothesis · Trophic relay · Wading birds


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