Tidal Migrations of Intertidal Salt Marsh Creek Nekton Examined with Underwater Video

摘要

Nekton tidal migration patterns were examined in oligo-mesohaline intertidal salt marsh creeks using underwater video observations collected throughout multiple tidal cycles (i.e., flood-ebb) during summer 2005–2006. Underwater video observations indicated that species composition and abundances varied with tide stage. Three intertidal salt marsh species (Fundulus heteroclitus, Morone americana, Menidia menidia) were the most abundant species observed. In general, resident species were most abundant in early flood and late ebb tide stages, whereas transient species were most abundant around slack high tide. F. heteroclitus displayed a consistent symmetrical tidal migration pattern and primarily occurred in early flood and late ebb tide stages. M. americana occurred throughout flood and high tides, but were largely absent from intertidal creeks during ebb tide. M. menidia was observed during all tide stages, but displayed no distinct migration patterns. The results of this study highlight the advantages and disadvantages of using underwater video for examining small-scale tidal migrations of nekton in intertidal salt marsh creeks.