Postmortaal onderzoek van bruinvissen (Phocoena phocoena) uit Nederlandse wateren, 2021: Biologische gegevens, gezondheidsstatus en doodsoorzaken

This annual report presents the results of post-mortem examinations of stranded harbour porpoises in 2021. One of the main objectives of the research is to quantify human-induced causes of death. In 2021, 54 dead harbour porpoises were examined: 35 males and 19 females, comprising 24 adults, 23 juveniles and 7 neonates. In addition three foetuses found, examined and sampled. Most of the examined harbour porpoises died as a result of infectious diseases (39%) and grey seal attacks (20%). Bycatch was the most likely cause of death of 7 porpoises (13%) and 5 other porpoises died following trauma of unclear origin (9%).