Modeling the social and ecological effects of climate change on the US Atlantic sea scallop fishery

Abstract:

Global change caused by human activity is profoundly altering natural systems worldwide, with varying consequences for human communities. Ocean acidification, the reduction in ocean pH and carbonate ion levels caused by anthropogenically released carbon dioxide, has caused large economic losses for the Pacific Northwest oyster industry and concerns exist that similar economic losses could occur for other shellfish fisheries in the near future. The US Atlantic Sea Scallop (Placopecten magellanicus) fishery is one of the most valuable wild-caught fisheries in the US, bringing in $559 million USD in ex-vessel revenue in 2012. Although the fishery is well managed on a short-term basis, climate-related changes such as warming and ocean acidification are not currently included in management practices. To explore the intersection of fisheries management and environmental change, we developed an integrated assessment model for the US Atlantic sea scallop industry that incorporates ocean biogeochemistry, sea scallop population dynamics, and harvests, based on socio-economic interactions. We developed future scenarios relevant for the fishery based on the Intergovernmental Panel on Climate Change representative concentration pathways that include changing ocean chemistry and temperature, fishery operating costs, and market demand. We use these scenarios to examine the impacts of climate change on future scallop populations, landings, revenues, and income, and we test the effects of alternative management practices. The model results suggest if that ocean acidification slows growth and increases mortality, it is likely to reduce biomass and change the population size distribution which leads to large losses in landings and revenue compared to present day. Testing alternative management strategies suggests that under future conditions, decisions must be made to maintain either sustainable biomass or the present economic value of the industry; preserving both may not be possible in a warming, acidifying ocean.