We had a chat with Dr Chiara G. Bertulli who works as Sightings Officer at Sea Watch in response to the news of ‘Benny’ the Beluga whale being in the Thames.
I have following the news of the lone beluga whale sighted in the Thames estuary very attentively since Tuesday.
I was sceptical at first, and I asked myself: it really a beluga whale? But as soon as I had a glimpse at the images and video footage of the whale reported on social media, I recognised white colouration, the rounded head and the lack of dorsal fin, and I knew it was a ‘white whale’!
You may think it strange to encounter this species in UK waters, and I do agree with you. However, in the last half century, the species has been sighted 17 times in Britain and Ireland (ten in the last thirty years). This species was also sighted in 2015 (during the 9-day event called National Whale and Dolphin Watch organized by Sea Watch) below the cliffs off Dunseverick in Northern Ireland, where the white whale arching its back left everyone speechless.
Truth is, cetacean species have observed changing their home ranges responding to changes in the marine environment which have altered the distribution and abundance of many marine species more and more in the last decade. Consequently, warm-water cetacean species have been recorded in increasing numbers, and some arctic species have been recorded outside of their normal habitat. I am sure everyone remembers the first ever reported case in Europe of a bowhead whale – a species which is largely confined to the Arctic regions – which was a sighting off the Isles of Scilly in February 2015.
So, what brings this individual such a distance from the arctic into our waters? With regards to the unusual sighting of the bowhead whale, I thought that the fragmentation of floating ice may have resulted in a whale typically associated with pack ice, straying much further south. I am not sure though if the same has occurred in the case of this beluga. It could also be that the storm which hit the British Isles days ago forced the animal south of its usual habitat. The species in the eastern North Atlantic typically occurs in the Barents Sea north and east of Norway, but animals do exhibit some southwards movement to coastal waters of northern Norway seasonally in early autumn.
The important thing now is to keep monitoring the animal’s behaviour and movement. The good news is that the beluga is feeding, it has been feeding around barges on the river the whole day yesterday.
My concerns are though that the animal might not be able to find its way out to the open sea and that it might not be able to cope alone without the pod to help and protect him. In addition to that, there is a lot of boat traffic in the river Thames and I am also worried is that the animal might not react well under so much anthropogenic disturbance. Belugas are species typical of shallow coastal areas including estuaries, the major threat to the animal comes from humans. So, I would urge the media and the public to keep a safe distance, no to stress the animal.
Dr Chiara G. Bertulli is the Sightings Officer at Sea Watch Foundation. She holds a PhD in marine biology from the University of Iceland. Before joining Sea Watch she spent eight years leading a citizen science project focusing on the conservation, demography, social structure and health status of minke whales and white-beaked dolphins in Iceland.