Dear MARMAM community, We are pleased to share our recent open-access publication about the effectiveness of pingers in bycatch mitigation of the endangered Black Sea harbour porpoise. Popov D, Meshkova G, Dimitrov H, Panayotova M (2026) Can pingers mitigate the bycatch of the endangered Black Sea Harbour Porpoise? Nature Conservation 63: 1-15. https://doi.org/10.3897/natureconservation.63.183768 *Abstract* Incidental catch in fishing gear, mainly in bottom-set gillnets targeting turbot, is a major mortality factor for the Black Sea harbour porpoise (/Phocoena phocoena relicta/), an endangered endemic subspecies of cetacean. Acoustic deterrent devices or pingers are widely used to mitigate bycatch. Between 2019 and 2022, trials using three different pinger models (Future Oceans 10 kHz, Future Oceans 70 kHz, and PAL Wideband) were conducted in Bulgaria during standard turbot fishing operations. The study encompassed a total of 57 hauls. Data was collected by onboard observers (79% of all hauls) and through self-reporting by fishermen. In 61% of all hauls, bycatch was observed, accounting for 189 cetaceans: 182 harbour porpoises, 5 bottlenose dolphins, and 2 common dolphins. No significant difference in bycatch rates between active and control nets (one haul each per trial) was observed in trials involving Future Oceans 10 kHz (17 trials) and 70 kHz (6 trials) pingers (U test, p > 0.05). However, a significant reduction in cetaceans’ bycatch of 74% was recorded during the 6 trials conducted with PAL Wideband pingers (U test, p < 0.05). We therefore recommend PAL as a suitable bycatch mitigation device to Bulgarian authorities and the General Fisheries Commission of the Mediterranean. Best regards, Dimitar Popov -- __________________________________________________ *__________________________________________________ **Mr. Dimitar Popov**,**PhD **Project Coordinator GREEN BALKANS - Stara Zagora NGO* BSB00432 EOL 30, Boruygrad str. Stara Zagora 6000, Bulgaria Mobile +359 (0)885 108712 E-mail: _dpopov@greenbalkans.org_ http://www.greenbalkans.org __________________________________________________