Management Can Make Shark Fisheries Sustainable: Evidence From Long‐Term Surveys

ABSTRACT

Sustainable management of shark fisheries is challenging because sharks are highly vulnerable to fishing mortality. By analysing data from three independent scientific surveys between the early 1970s and late 2000s across three fishing regions in southern Australia, we show that conservative fisheries management following severe depletion facilitated full stock recovery of the gummy shark ( Mustelus antarcticus ), a species of moderate biological productivity. Conversely, the school shark ( Galeorhinus galeus ), a species of particularly low productivity, showed little sign of recovery, despite low levels of immigration from New Zealand, and recruitment likely collapsed during the first decade of the present century in response to the Millennium Drought. Only very recently have independent, innovative close‐kin mark‐recapture techniques demonstrated a rise in the school shark stock. The results indicate that management controls can successfully rebuild some shark stocks, but outcomes vary among species. Effective shark fisheries management requires species‐specific regulation and continued fishery‐independent monitoring covering all sizes to detect depletion, recovery and emerging pressures such as climate change.