Acta Ichthyologica et Piscatoria 50(4): 401-411, doi: 10.3750/AIEP/03033
Updating records of Squatina aculeata (Elasmobranchii: Squatiniformes: Squatinidae) in the Mediterranean Sea
expand article infoB. Zava, G. Insacco, M. Corsini-Foka, F. Serena
Open Access
Abstract
Background. The decline of the populations of the three Critically Endangered species Squatina aculeata Cuvier, 1829, Squatina oculata Bonaparte, 1840, and Squatina squatina (Linnaeus, 1758) in the Mediterranean basin is mainly attributed to overexploitation by demersal fisheries, in particular bottom trawls, but also artisanal and recreational. The survey of their occurrence in the basin in parallel with the collection of biological information are essential in order to develop or improve conservation strategies. For that reason, the presently reported study aimed to enrich knowledge on today’s distribution and biology of one of the above-mentioned endangered species, S. aculeata. Materials and methods. Information on the incidental capture of twenty specimens of S. aculeata in various Mediterranean regions was provided between 2011 and 2020 by professional fishermen and citizen scientists. Thirteen specimens were identified through examination of photos taken directly on board, or at the fish market while seven specimens were deposited at scientific collections and studied in the laboratory. Sex, total length, and total weight were determined, whenever possible. The TW–TL relation was calculated and the stomach content of one specimen was examined. Results. The findings document the presence of this rare and endangered angelshark in the deep waters of a wide area of the Mediterranean covering six Geographical Subareas (GSAs) of the General Fisheries Commission for the Mediterranean (GFCM), from the west to the central and eastern sectors of the basin. The total length in 17 individuals ranged from 54 cm to 190 cm, the total weight in 12 individuals from 2100 g to 49 000 g. Fifteen specimens were caught by bottom trawlers, four by trammel nets, one with longline. Conclusion. The reported recent findings document the occurrence of S. aculeata in various Mediterranean areas, some of which lacked records for many years. A continuous survey on the occurrence of this endangered species is recommended in order to assess the actual status of its population, but also of huge importance is the improvement of fishermen education and awareness aimed at the protection of the species as well as the inflexible application of international recommendations and regulations both for the professional and non-professional or recreational fishery.
Keywords
angel shark, distribution, length–weight relation, Critically Endangered species