A fish’s-eye-view: accessible tools to document shellfish farms as marine habitat in New Jersey, USA

Abstract

Shellfish growers routinely observe fish and invertebrates interacting with their aquaculture gear. To quantitatively assess these interactions, underwater action cameras (GoPro (R)) were used to document fish and invertebrate activity in and around floating oyster bags, cages, and a natural marsh habitat on an oyster farm in the Little Egg Harbor region of Barnegat Bay, New Jersey, USA, in 2018. A free and open-source event-logging software was used to analyze video files. A total of 21 species from 4 phyla were identified across all days and sites. Nekton were quantified from continuously recorded video using the MaxN abundance metric, defined as the maximum number of individuals of a given species present within each 1 min segment of video. Species of both ecological and economic importance in the local ecosystem used the 3 intertidal habitats. Abundance and community composition observed around oyster cages differed from that around floating oyster bags and marsh edge; the latter 2 habitats were not significantly different. Juvenile fish were frequently observed, suggesting that the oyster farm may provide similar natural history functions as other natural marsh habitat.