The Collection of River Herring Bycatch Information from the Rhode Island Small-Mesh Bottom Trawl Fishery: Explicative Data with Management Implications

The collection of catch and effort information from high-volume small-pelagic fisheries in the Northwest Atlantic has been given increased emphasis in recent years due to concerns over the bycatch of river herring. The Massachusetts Division of Marine Fisheries has been sampling the landings of the Rhode Island small-mesh bottom trawl (SMBT) Atlantic herring and mackerel fisheries since 2011. Between our port-side sampling program and two federally operated at-sea observer programs, over 50% of SMBT landed trips were sampled in 2012 and 2013. In addition to catch and effort information, our port-side sampling program collected large quantities of river herring data including: lengths, individual weights, age structures and tissue samples for genetic analysis. An estimate of fleet-wide river herring bycatch was calculated for both years and demonstrated inconsistent inter-annual spatiotemporal patterns and catch rates. Preliminary results of ageing data show a bi-modal age structure for blueback herring over a large spatial area suggesting a truncation of growth that could be indicative of separate sub stocks. With the deepening concerns over river herring bycatch, and the increasing pressure on managers to regulate these fisheries, these data are likely to be instrumental as new management actions are developed and implemented.