Estimates of cetacean abundance in European Atlantic waters in summer 2022 from the SCANS-IV aerial and shipboard surveys - Rapport final (septembre 2023)

The Small Cetaceans in European Atlantic waters and the North Sea surveys (SCANS) are regionally coordinated synoptic surveys that started almost 30 years ago with the aim of monitoring whales, dolphins and porpoises on the shelf and offshore waters of the European Atlantic.

The objective of the SCANS-IV project is to estimate the abundance of cetacean species in shelf and oceanic waters of the European Atlantic through a large-scale multinational aerial and shipboard survey in the summer of 2022. This is the most appropriate survey timing because of the higher probability of good sighting conditions, and also to ensure that results are comparable with those from previous SCANS surveys conducted in 1994, 2005/2007 and 2016 (Hammond et al. 2002, 2013, 2021).

The project will be achieved through the successful completion of six work packages (WP, Appendix 1). The first two WPs (WP1 & WP2) focus on collecting data on cetacean abundance and distribution through implementation of aerial surveys on the continental shelf and shipboard surveys in offshore waters. The data will be analysed in WP3 to generate abundance estimates, trends and perform spatial habitat modelling. WP4 will consider the long-term security of the large-scale cetacean monitoring SCANS programme in the Northeast Atlantic and propose a governance structure to ensure the continuation into the future. WPs 5 & 6 will focus on dissemination of results, project management and reporting.

This report summarises design-based estimates of abundance for those cetacean species for which sufficient data were obtained during SCANS-IV: harbour porpoise (Phocoena phocoena), bottlenose dolphin (Tursiops truncatus), Risso’s dolphin (Grampus griseus), white-beaked dolphin (Lagenorhynchus albirostris), white-sided dolphin (Lagenorhynchus acutus), short-beaked common dolphin (Delphinus delphis), striped dolphin (Stenella coeruleoalba), long-finned pilot whale (Globicephala melas), beaked whales (all species combined; Cuvier’s beaked whale (Ziphius cavirostris), Sowerby’s beaked whale (Mesoplodon bidens) and unidentified beaked whale), fin whale (Balaenoptera physalus) and minke whale (Balaenoptera acutorostrata).