Initial Response of Fishes to Marsh Restoration at a Former Salt Hay Farm Bordering Delaware Bay

Abstract

The success of salt marsh restoration, especially as it relates to the structural and functional role of fish populations, is poorly defined. In order to evaluate the effectiveness of the restoration of a former salt hay farm toward a functional marsh, we monitored the fish response to the restoration (resumed tidal flow, creation of creeks) from September 1996 to November 1997 and compared that to the prerestoration condition. During the post-restoration period we compared fish species richness, abundance, composition and size during the spring, summer and fall between the restored site and an adjacent reference marsh with similar physical characteristics (temperature, salinity, dissolved oxygen, depth, distance from the bay). Fish populations, primarily young-of-the-year, were characterized at both sites by monthly sampling with replicate (4 tows per site, 2 sites in each of two creeks) daytime otter trawls (4.9 m, 6 mm cod end mesh, n=375 two-minute tows) in large marsh creeks and with weirs (2.0 m×1.5 m×1.5 m, with 5.0 m×1.5 m wings, 6.0 mm mesh, n=48) in smaller intertidal marsh creeks (2 sites in the restored marsh, 4 sites in reference marshes). Based on these observations, fish abundance was greater in the restored creeks while species richness, species composition, and average size of fishes were similar to the reference site. An analysis of fish assemblages at the same sites indicated that the reference and restored marshes were similar for large and small marsh creeks. Where differences occurred it was often the result of greater abundances of selected species at the restored marsh. Also, during this period the standing stock at the restored marsh may have exceeded that for the reference marsh. Thus, it appears that the fish responded quickly to the restoration.KeywordsSalt MarshReference SiteFish AssemblageOtter TrawlReference MarshThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.