Encounters with threatened batoids from the perspective of a spearfisherman suggesting an aggregation site in southeastern Aegean Sea, Turkey

Seasonal aggregations of batoids were observed in Güllük Bay (souteastern Aegean Sea) based on opportunistic underwater observations between the years of 2014–2022. Torpedo marmorata, Glaucostegus cemiculus, Dasyatis pastinaca, Gymnura altavela and Aetomylaeus bovinus were observed in the study area. The most observed species is G. altavela (n=65) and it constitutes 51.18 percent of the whole sample, and followed by A. bovinus (n=31, 24.4%), D. pastinaca (n=12, 9.44%), G. cemiculus (n=8, 6.29%) and T. marmorata (n=2, 1.57%). Based on the seasonal occurrence data of batoids observed during the research, it is seen that the species that occurred in the region from mid-spring to mid-autumn, and the aggregations peaked in July. Seasonal aggregations of batoids may have important implications for the conservation of these species. Among the observed batoids in the present study, only G. cemiculus is currently under protection in Turkey. According to EU Regulation 1343/2011 and Annex II of the Barcelona Convention, G. altavela is a prohibited species; thus, it should not be retained on board, transhipped, landed, transferred, stored, sold or displayed or offered for sale, and masters of fishing vessels shall record in the fishing logbook any event of incidental catch and release. Therefore, as an urgent measure, at least G. altavela and A. bovinus, which are considered as “critically endangered”, should be added to the list of protected species in Turkish waters, and the aggregation site in Güllük Bay should be declared as a no-take-zone during mid-spring and throughout the summer.