Introduction Population abundance is amongst the most basic and crucial parameters for the assessment of conservation status of any species. Three species of odontocetes, all represented by local subspecies, inhabit the Black Sea: the Black Sea common dolphin Delphinus delphis ponticus , the Black Sea bottlenose dolphin Tursiops truncatus ponticus , and the Black Sea harbour porpoise Phocoena phocoena relicta . Their populatio...

Incidental catch in fishing gear (often known as bycatch) is a major mortality factor for the Black Sea harbour porpoise ( Phocoena phocoena relicta ), an endemic subspecies listed as Endangered in the IUCN Red List. The primary gear, responsible for porpoise bycatch in the Black Sea are bottom gillnets and trammel nets targeting turbot ( Scophthalmus spp.), the most valuable commercial fish species in the Black Sea. From 2019...