The baby whale escaped an inflatable cushion that was guiding it from the River Thames to safety.
Rescuers are attempting to catch a whale stranded in the River Thames in south west London for the second time.
The whale, believed to be a baby minke, was first spotted on Sunday near Barnes Bridge.
RNLI teams managed to save the whale but it escaped an inflatable cushion that was guiding it while it was being towed to safety at 01:00 BST.
Throughout Monday it has been swimming between Richmond and a few miles along the river in Teddington.
It is believed the whale may have some injuries.
image copyrightReuters
A spokeswoman for the RNLI said when crews had been moving the whale to a deeper part of the Thames, it was “displaying concerning behaviours and experts in attendance were concerned that it may be unwell”.
Glen Nicolaides from London Fire Brigade said before its escape, the whale was in the process of being moved to a more stable location where it would be assessed to determine the scale of its injuries and whether it could be released.
The BBC’s Matt Graveling, at the scene earlier, said the future of the whale “still hangs in the balance”.
image copyrightPA Media
image copyrightPA Media
Liz Sandeman, co-founder of Marine Connection, said the welfare of the animal had to be considered as it was not just a case of getting it back to sea if it was a young animal.
“It wouldn’t know how to feed. It learns everything from its mother – how to navigate, how to hunt – and that whale is a young whale,” she said.
The Port of London Authority, which owns and operates the lock, said the whale had become stranded at about 19:00 BST. After being spotted by Barnes bridge, it became stuck on Richmond Lock’s boat rollers.
RNLI rescuers arrived at about 21:00 to help the animal, which is approximately 3-4m (10-13ft) long, off the concrete.
They were joined by fire crews and marine rescue divers, who tried for several hours to float the whale.
The lock is situated between Teddington and Richmond, comprising of three vertical steel gates suspended from a footbridge.
image copyrightMatt Graveling
Jake Manketo, 20, from Richmond, said: “Everyone here is just hoping they get it out.
“We couldn’t believe our eyes when we first saw the poor fella, not every day something like this happens in Richmond.”
Minke whales are the smallest of the great whales, growing to about 10m (33ft) and can usually be found throughout the northern Atlantic and Pacific Oceans.
Their range extends from the ice edge in the Arctic during the summer to near the equator during winter.
image copyrightReuters
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