Data from: Satellite telemetry reveals higher fishing mortality rates than previously estimated, suggesting overfishing of an apex marine predator

Overfishing is a primary cause of population declines for many shark
species of conservation concern. However, means of obtaining information
on fishery interactions and mortality, necessary for the development of
successful conservation strategies, are often fisheries-dependent and of
questionable quality for many species of commercially exploited pelagic
sharks. We used satellite telemetry as a fisheries-independent tool to
document fisheries interactions, and quantify fishing mortality of the
highly migratory shortfin mako shark (Isurus oxyrinchus) in the western
North Atlantic Ocean. Forty satellite-tagged shortfin mako sharks tracked
over 3 years entered the Exclusive Economic Zones of 19 countries and were
harvested in fisheries of five countries, with 30% of tagged sharks
harvested. Our tagging-derived estimates of instantaneous fishing
mortality rates (F = 0.19–0.56) were 10-fold higher than previous
estimates from fisheries-dependent data (approx. 0.015–0.024), suggesting
data used in stock assessments may considerably underestimate fishing
mortality. Additionally, our estimates of F were greater than those
associated with maximum sustainable yield, suggesting a state of
overfishing. This information has direct application to evaluations of
stock status and for effective management of populations, and thus
satellite tagging studies have potential to provide more accurate
estimates of fishing mortality and survival than traditional
fisheries-dependent methodology.