New theory on mass strandings in pilot whales includes Falklands experiment — MercoPress

New theory on mass strandings in pilot whales includes Falklands experiment

Thursday, September 1, 2022 – 14:18 UTC

At sea, cetaceans form family groups, which include several generations of pilot whales, all related to a single female.

Mass strandings in cetaceans – a group of marine mammals including the whale, dolphin and porpoise – have been reported since the time of Aristotle and there has been a long way to understand what causes them. Pilot whales, a gregarious species with complex social ties, are most often affected.

Recent genetic analysis in the northern and southern hemispheres, in the Falkland Islands, by a team including academics from Aberystwyth University challenges existing thinking about the role of social behaviors in the mass strandings of these animals .

At sea, they form family units called pods. In a group, there are several generations of pilot whales which are all linked to a single female. It was therefore long thought that mass strandings could be caused by family members trying to stay together.

However, the data reveals that in most cases each mass stranding involved multiple unrelated pods, rather than a single pod as previously thought. This suggests that family breakdown, rather than family cohesion, may be a major cause of these events.

The new research has implications for how rescues are attempted: Assuming all stranded animals were related may have undermined previous efforts, as the intentional rescue of unrelated animals may contribute to restrandings.

One of the research team, Dr Niall McKeown, Lecturer in Marine Biology at Aberystwyth University, said: “The assembled team worked together to obtain and genetically analyze samples of mass strandings for the first time in the northeast Atlantic and the Falkland Islands. The results provide further evidence that there may be a mixture of family units at some point during the processes of It remains to be seen to what extent this is a cause or consequence of mass strandings.

As well as academics from Aberystwyth University, the project also includes researchers from the Falkland Islands Fisheries Department, the Universities of Glasgow, Chester, Utrecht, Galway-Mayo Institute of Technology and Scottish Marine Animal Stranding Scheme.

Dr McKeown added: “Our study shows mixed family groups within a mass stranding event. It may also reflect a more complex social society than that assumed for long-finned pilot whales. Further research will help disentangle these factors and will be of great relevance to rescue strategies.

Sharon D. Cole