Quantifying and predicting responses to a US West Coast salmon fishery closure

As anthropogenic changes interact with natural climate cycles, the variability of marine ecosystems is likely to increase. Changes in productivity of particular fisheries might be expected to lead not only to direct impacts within a fishery but to economic and ecological effects on other fisheries if there is substantial cross-participation by fishers. We use data from the US West Coast salmon troll fishery before, during, and after a large-scale closure to illustrate how altered resource availability influences the behaviour of fishing vessels in heterogeneous ways. We find that vessels were less likely to participate in fishing of any type during the closure, with >40% of vessels ceasing fishing temporarily and 17% exiting permanently. Vessels that were more dependent on salmon were more likely to cease fishing while more diversified vessels were more likely to continue. In spite of a high level of cross-participation, we find limited evidence that vessels increased their participation in other fisheries to offset lost salmon revenue. Ports that obtained more of their revenue from salmon troll vessels saw larger decreases in their revenue during the closure. Ocean conditions from 2013 to 2015 suggest the possibility of another highly restricted salmon fishing season in 2017. Our models predict that such restrictions would cause another economic disaster and lead to a large fraction of vessels exiting fishing but suggest that effects on fisheries linked by cross-participation are likely to be low.