Cartilaginous fish [sharks, skates, rays and chimaeras]

Abstract

EXECUTIVE SUMMARY -- A first Red List of cartilaginous fish (sharks, skates, rays and chimaeras), showing risk of extinction, is presented for Irish waters -- Of the cartilaginous fish occurring in Irish waters, 58 were assessed using the latest IUCN categories. -- Of these, 6 were assessed as Critically Endangered: Portuguese dogfish Centroscymnus coelolepis; common (blue) skate Dipturus batis (= flossada); flapper skate Dipturus intermedia; porbeagle shark Lamna nasus; white skate Rostroraja alba and angel shark Squatina squatina. -- A further 5 species were assessed as Endangered: leafscale gulper shark Centrophorus squamosus; basking shark Cetorhinus maximus; common stingray Dasyatis pastinaca; undulate skate Raja undulata and spurdog Squalus acanthias. -- An additional 6 species were assessed to be Vulnerable: longnose velvet dogfish Centroselachus crepidater; kitefin shark Dalatias licha; tope Galeorhinus galeus; shagreen ray Leucoraja fullonica; longnose skate Dipturus oxyrinchus and cuckoo ray Leucoraja naevus. -- Of the remaining species, 19 were assessed as Near Threatened and 22 species as Least Concern. The main anthropogenic impacts on threatened species are over-exploitation by commercial fisheries and habitat destruction and disturbance. -- There are no longer any directed fisheries for any threatened cartilaginous fishin Irish waters. However threatened species are taken as by-catch in several fisheries, involving both Irish and non-Irish vessels. Similarly, endangered and threatened species that straddle Irish and non-Irish waters are caught by fleets further afield.