Working Group on Elasmobranch Fishes (WGEF)

• Main Author: ICES
• Format: Text
• Language: English
• Published: ICES 2021
• Subjects: envir; geo; Northeast Atlantic
• Online Access: https://doi.org/10.17895/ices.pub.8199; https://archimer.ifremer.fr/doc/00743/85492/90603.pdf; https://archimer.ifremer.fr/doc/00743/85492/

ICES WGEF meets annually and is responsible for providing assessments and advice on the state of the stocks of sharks, skates, and rays throughout the ICES area. In 2021, WGEF provided ad-vice for 16 stocks of rays and skates distributed the North Sea ecoregion, the Azores and MAR; catsharks (Scyliorhinidae) in the Greater North Sea, Celtic Seas and Bay of Biscay and Iberian Coast ecoregions; smooth-hounds in the Northeast Atlantic; and tope shark in the Northeast At-lantic. Despite improvements of reported landings in the past decade, quality check and error correc-tions, reliable time-series of landings do not span more than 10–12 years for most stocks. Esti-mated discards are uncertain because elasmobranchs are mostly bycatch in all types of fisheries and national sampling effort might be insufficient for estimating precise and unbiased discards for elasmobranchs. Further, survival of discarded elasmobranchs is thought to be high but quan-titative estimates are scarce so that the relationship between discards and dead catches is un-known. As a consequence, for numerous stocks it is not possible to provide catch advice. For those stocks, advice on landings is formulated. The majority of WGEF stocks are assessed as Category 3 stocks, i.e. the advice is based on trends derived from scientific surveys. In November 2020, a workshop (WKSKATE) was held to evalu-ate criteria for the representativeness of surveys as well as to standardize and revise methods for calculating stock size indicators. Recommendations from WKSKATE were reviewed by the group and applied to the assessments where deemed appropriate. Consequently, for three stocks i.e. thornback ray and lesser spotted dogfish in the greater North Sea (rjc.27.3a47d and syc.27.3a47d) and smooth-hound in the ICES area (sdv.27.nea) surveys were added to the assess-ment, while for spotted ray in the North Sea (rjm.27.3a47d) the UK(E&W)–BTS–Q3 was excluded. For those stocks classified as ICES category 5 and 6 stocks, i.e. for which even survey data are lacking and ...