The use of spearfishing competition data in fisheries management: Evidence for a hidden near collapse of a coastal fish community of Galicia (NE Atlantic Ocean)

Abstract

The use of commercial catch statistics to estimate overfishing consequences has been criticised, but alternative long-term data sets are rare. Long time-series data sets from recreational fisheries competitions have been used to infer trends in coastal fish communities. Here an historic archive (1953-2007) of recreational spear fisheries in Galicia (NW Spain) was employed to estimate long-term changes in coastal ecosystems. Using generalised additive regression models, decreases in the abundances of coastal rocky reef fishes of up to 76% over the last 50 years were found. In the same period, the mean body weight also decreased by 76%. In addition, relative catch frequency has decreased for the most valuable commercial species. Overfishing, amongst other human impacts, has brought these ecosystems so close to collapse that it is urgent to implement measures to ensure their recovery.