Cuvier’s beaked whale live strands on Mull
The Cuvier’s beaked whale stranded on Calgary Bay over Hogmanay
Just hours before 2019 began, members of the HWDT team – who have undergone training with British Divers Marine Life Rescue (BDMLR) - responded to assist a stranded Cuvier’s beaked whale at Calgary Bay, a popular beach in the north west of Mull. The whale live stranded on the sand, but sadly perished shortly after dusk on Hogmanay.
Live strandings of Cuvier’s beaked whales are a rarity in Scotland, so the folks from the Scottish Marine Animal Strandings team (SMASS) wasted no time, travelling down to Mull to examine the whale in order to try and establish cause of death.
“While strandings, particularly live strandings, can be emotionally charged and distressing for those involved, they also provide a unique opportunity to examine rare species which are difficult to study in the wild.”
From initial analysis undertaken by SMASS, the mature male whale seems to have died of natural causes, likely from an infection with a worm.
“It was almost immediately clear why this animal stranded - it had been very ill indeed, with a peritonitis and what appeared to be a multi-organ disseminated bacterial infection.
Looking closer however, the underlying cause seemed to be a chronic verminous arteritis, which was most likely due to infection with a nematode called Crassicauda.
We are awaiting bacteriological and histopathology results on this, but I think this is the ultimate cause for this old whale’s eventual demise.”
Cuvier’s beaked whales are widely distributed throughout all major oceans (apart from polar seas), with Scotland representing their northern-most limit. Live sightings in the Hebrides are very rare, and so it doesn’t come as a surprise, that we haven’t been able to confirm any live sightings with photos through Whale Track yet. Instead, they inhabit the deeper waters off the continental shelf further out into the Atlantic Ocean. However, numerous stranded animals indicate that they may be more common than sightings data suggest.
Last year, 96 beaked whales, mostly Cuvier’s beaked whales, washed up along the west coast of Scotland, Ireland and Northern Ireland. This represents the largest unusual mortality event (UME) recorded for this species ever, anywhere in the world. The team at SMASS are still in the process of investigating potential causes. The Cuvier’s beaked whale that washed up on Calgary is not linked to this UME.
This most recent stranding, serves a reminder that even in the depths of winter, whales, dolphins and porpoises inhabit the waters surrounding the Hebrides, and there are so many mysteries linked to them that we are still to uncover. Since welcoming in the New Year, 22 live sightings have been reported to HWDT through Whale Track, including 15 sightings of harbour porpoises. Every one of these sightings is important for research, so please do continue to keep an eye out for activity and please do submit your sightings either online or through the Whale Track app. What’s more, if you come across a live stranded animal while on the coast, please contact BDMLR (http://www.bdmlr.org.uk). Alternatively, if you discover a marine animal carcass on the shore, please report your find to SMASS (http://www.strandings.org/).
Finally, we would like say a big thank you to the community of people who gathered together on a cold, wet and windy Hogmanay, providing valuable support during the live stranding and subsequent necropsy, this includes and is not limited to BDMLR, SMASS, Tobermory and Craignure Coastguard teams, Mull Aquarium, Joseph Golledge and the Reade family.