SCIENTISTS conducting post-mortem examinations after a mass whale stranding have provided an update on what may have caused the tragic incident.
The entire pod of 55 pilot whales washed up on Traigh Mhòr beach at North Tolsta on the Isle of Lewis early on Sunday morning.
After attempts to refloat one of the more active whales resulted in it restranding, the decision was taken to euthanise the remaining whales.
The British Divers Marine Life Rescue initially stated that they believed one of the dead whales had a vaginal prolapse, which may have led to the rest of the pod following her onto shore during birthing troubles.
However, researchers from the Scottish Marine Animal Stranding Scheme (SMASS) have since carried out post-mortem examinations on “three of the top priority animals” and corrected that assessment.
They said: “The most interesting finding was a large adult female that has what was first thought to be a prolapse but further investigations showed to be the placenta, highlighting issues with birthing.
“This would have caused obvious stress to the individual, and due to the close family ties of this species, could have potential further significance for all of the members of the pod.
“Further analysis over the next several days will help us to better understand what happened.”
The SMASS team have now been joined by researchers from the Netherlands to help with the necropsy work.
They say they are focusing on doing as many necropsies (animal autopsies) as possible, with more potential answers on what caused the stranding likely to be announced in the coming weeks.
Angus MacNeil, MP for Na h-Eileanan an Iar, called on Marine Scotland to “urgently” assess sonar work taking place in the seas around Lewis.
However, a spokesperson from the Scottish Association for Marine Science said it would be “premature to speculate” on what may have caused the stranding until the investigation has been concluded.
They said: “Long-finned pilot whales are an open-seas species that are normally rarely encountered in shallow coastal waters around the UK.
“As noted by colleagues from the Scottish Marine Animal Stranding Scheme, who are currently dealing with this situation, the current mass stranding event is the largest recorded in UK waters in terms of casualties, although it is important to note that similar events have happened previously, most recently in 2011 (near Durness) and 2015 (Isle of Skye).
“It would be premature to speculate on precise causes of the mass stranding event until the SMASS team have completed their investigations. These would involve necropsies (post-mortem examinations) of the carcases to see if they were suffering from illnesses or injuries that might have led to the strandings.”
They added: “Many things can lead to whales and dolphins coming ashore, with disease, disorientation in complex inshore environments, and underwater noise being examples of factors that could lead to such an event."
Updates on how the post mortem examinations are progressing can be found on the SMASS and Stranding Research Instagram pages – although readers are warned they contain graphic images of the whales.
The public is encouraged to report live-stranded whales, dolphin or similar species to the British Divers Marine Life Rescue hotline on 01852-765546 or the SSPCA helpline on 0300-999999.
Dead animals should be reported to SMASS.
