How does a whale find itself 90 miles from sea? And are such incidents becoming more common?

The minke whale, scientific name Balaenoptera acutorostrata, is the most common whale species in UK waters. Females reach up to 8.5 metres in length; males about 8 metres. They weigh between five to 10 tonnes. They are black, brown or dark grey on their backs and lighter below.

The whale, a juvenile of 4 metres in length, was found at Richmond lock, about 90 miles from the sea. The last minke whale in the Thames was found in 2019, in Battersea.

Minke whales are common in the UK, in open water. The juvenile minke could have been separated from its mother and become disorientated in the enclosed estuary.

Reporting of strandings of cetaceans (whales, dolphins and porpoises) have been on the increase for the past five years, according to the Cetacean Strandings Investigation Programme, run by the Zoological Society of London. CSIP scientists believe the increase is due to increased awareness and ability to report, rather than a rise in numbers. Strandings usually happen in the north-east or south-est of England, where there are large bodies of water. River strandings are unusual.

There were more than 18,000 strandings between 1990 and today, according to the CSIP. Most common were harbour porpoise, dolphins, followed by pilot whales and minke whales. Most of the time, an animal will have died of natural causes such as infectious diseases or starvation. They can also be found entangled in fishing nets and lines.