Angling records track the near extirpation of angel shark Squatina squatina from two Irish hotspots

Abstract

The angel shark Squatina squatina was historically common in coastal waters from the British Isles to north-western Africa, including the Mediterranean. Reported commercial landings from northern Europe reduced to near-zero before the species was added to the EU Prohibited Species list and subsequently listed as Critically Endangered by the IUCN. S. squatina is encountered rarely in offshore trawl surveys, probably because of low spatial overlap with coastal populations and habitats. An alternative source of monitoring data is angling vessels, which can operate in discrete inshore areas. Analyses of 2 unique > 40 yr time series of angler tagging and specimen catch data from Irish waters, with catch and effort records from voluntary charter angling logbooks, reveal a sharp decline in S. squatina catches. Only 1 individual has been tagged since 2011. Almost all reports were from Tralee Bay and Clew Bay (western Ireland), where anecdotal sightings still occur. These historical hotspots may be significant to international angel shark conservation efforts.