Date of this Version
U.S. Government Work.
Although saltmarshes are thought to enhance the productivity of open estuarine water, 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 bio-mass budget to estimates 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 31.0 gm-2 saltmarsh, which falls within the range of previously reported values for estuarine fish communicates. 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.