Climate induced habitat changes in commercial fish stocks
Climate change is altering the distribution and abundance of fish species in ways not anticipated by current management policy. We aim to inform sustainable fisheries management by creating spatially-explicit, dynamic models of marine habitats that can improve stock assessments and project stocks into the future for thirty commercially important species on the Northeast Shelf. Improving upon methods used in the 2014 Butterfish stock assessment, we will expand the dimensions of habitat included in the models by integrating substrate, and seabed features along with the dynamic properties of the water column that change on daily to decadal time scales. We propose to develop the thermal-benthic habitat suitability index for thirty species and then project the suitable habitat into the future with downscaled earth system models. While studies projecting species temperature envelopes into the future have been done, they have rarely been explicitly developed to improve stock assessments or combined both the water column and seafloor to get a true picture of climate induced habitat changes. The work would provide direct benefit to management by identifying changes in the availability of populations to surveys, commercial fisheries, future bycatch issues, the potential need for quota reallocation, and highlighting stocks both leaving and entering new management areas. The suitable habitat will integrate the benthic features to determine how habitat will expand, shrink, and/or fragment in the future. With data from the Northeast Fishery Science Center (NEFSC) trawl survey, the NorthEast Area Monitoring and Assessment Program survey (NEAMAP), State surveys and the benthic information from the Northeast Regional Assessment, we will determine the mechanistic thermal-benthic habitat response curve for each species, and map out the spatial extent of the suitable habitat for different years and seasons with regional ocean models. The dynamic 3-D habitat models linking the water column with seafloor features for each species will then be projected into the future with downscaled earth system models to examine how future fish habitat will change, expand or fragment under future climate conditions. The current overlap of species as well as future overlap will be identified, highlighting potential regulatory changes needed as species move into new areas. The management implications include quota allocations, management jurisdictional changes, and bycatch impacts. Our proposal directly responds to NOAA’s goals as outlined in the Next Generation Strategic Plan. It primarily addresses objective one of the Healthy Oceans Goal, to Improved understanding of ecosystems to inform resource management decisions. The research would improve the understanding of the impacts of climate variability and change on habitat which directly regulates the abundance and distribution of managed fish stocks. Our intent is to utilize these current and historic data sets to improve the synthesis, analysis, and application of climate and marine ecosystem observations and monitoring information to improve fisheries management.