01.12.2025 – The dark side of fishing

Today on our trip we encountered the negative side of fishing. We headed out to the ocean as our Spotter spotted some Bottlenose dolphins (Tursiops truncatus) interacting with a fishing vessel catching Black Scabbardfish (Aphanopus carbo). Bottlenose dolphins like to steal the fish from the longlines of these fishing vessels. These longlines sadly due not catch only the target fish. Very often other animals are also caught and these are considered Bycatch. On this day one of these animals was a Blue shark (Prionace glauca). We encountered it dying at the surface of the ocean. Blue shark breath manly by actively swimming with a slightly open jaw. Like that fresh water can continuously pass through the gills and provide oxygen. Once on the hook of the longline that can’t do that anymore and in most of the cases die. As the fishermen don’t want them they are then tossed simply overboard. Bycatch is truly a big problem, as thousands of animals can die as bycatch over the year.

By Horst Schulte

Sightings of the day

Ribeira Brava

14:00 Bottlenose dolphins

Stenella

14:30 Bottlenose dolphins, Blainville’s beaked whales, Blue shark