'Benny' the Thames whale not showing signs of injury or distress
Concern is growing that the whale has not made it back to the sea - but at the moment it appears to be in good health.
Thursday 27 September 2018 19:07, UK
The beluga whale that has been in the Thames for three days is "not showing any signs of injury or distress", according to the Port of London Authority (PLA).
The rare whale, nicknamed Benny, was seen at midday on Thursday slightly upstream from its previous location off the shore of Gravesend in Kent.
The beluga is believed to be an older juvenile.
"On 26 September, BDMLR medics observed the whale swimming strongly in the Thames current," said Gavin Parsons, director of the British Divers Marine Life Rescue, in a joint statement with the PLA.
"It also exhibited foraging behaviour, likely feeding, as well as surfaced and dived consistent with a healthy animal", the statement added.
However, authorities are on standby should the whale get in trouble.
It appeared to have moved further up river towards London on Thursday morning, but by the afternoon was back in the same spot as previous days.
Concern is mounting among conservationists that the tide has not taken the animal back out to sea.
It is a rare visit for the beluga, a species that usually inhabits the coastlines of northern Scandinavia, Russia, Alaska and Canada.
It is unclear how the whale came to be in the Thames, with experts speculating that it could have followed a shoal of fish while hunting for food.
There have been 20 sightings of belugas around the UK coast, according to experts.
As adults they are pure white, but young are born grey and lose their greyness over their first seven years.
Three years ago, belugas were spotted off the coast of Northumberland and Northern Ireland but sightings are described as "extremely rare".
Martin Garside, from the Port of London Authority, said the whale "appears to be behaving in a similar way to yesterday".
Authorities are urging river users to avoid approaching the whale.
Tanya Ferry, environment manager for the PLA said: "We thank river users for their consideration in avoiding the area, and ask them to continue to do so.
"We are working closely with BDMLR and are in contact with other relevant wildlife welfare organisations".