Humpback whale spotted swimming in Thames in London

Creature seen diving and surfacing for hours in rare sighting

A humpback whale has been spotted swimming in the Thames in London.

Sightings of the marine mammal were reported in stretches of the river in east London over the weekend, prompting warnings to boats.

The British Divers Marine Life Rescue charity confirmed it had “observed the humpback whale in the Thames Estuary for just over three hours”.

It said the whale was “diving and surfacing at approximately five to six-minute intervals, slowly moving down river with the outgoing tide”.

“It seems to be doing fine,” added Julia Cable, national co-ordinator for the charity.

Pictures posted on social media appeared to show the whale in Dagenham, Rainham and Erith.

The Ports of London Authority (PLA) said there had been “numerous sightings” in London, Kent and Essex over the weekend.

Ms Cable said it was “very unusual” for for a humpback whale to be seen within the Thames Estuary. She added: “It’s very likely that it just made a navigational error.”

Richard Banner, who photographed the whale after it “came up alongside” his yacht, said: “In 50 years of sailing the River Thames [it’s the] first time I’ve met a whale there.”

The humpback is believed to have been first spotted on Saturday in Gravesend, near to the location where a beluga whale was first spotted in London last year. The beluga – later dubbed Benny – spent months swimming in the Thames before leaving the capital early this year.

Shipping operators have been warned of the presence of the humpback, which PLA spokesman Martin Garside said was thought to be between 5m and 10m in length.

He told The Independent: “We hope it swims out on the next tide but it has been with us for at least two days now.”

Mr Garside said about one whale a year made its way into the Thames, although it is the first time a humpback has been spotted in the river in London for a decade.

The animal is not thought to be injured or in distress.

Nature writer David Callahan, who saw the whale near Rainham, said it “looked to be about eight metres long” and was “remarkably undisturbed by container ships going up and down”.

Humpbacks, which can grow to up to 18m in length and weigh 40 tonnes, are found in oceans across the world. They are sighted only sporadically in the UK, usually off the coast of Scotland.

In 2006, a northern bottlenose whale was spotted in the Thames in central London.

The whale, which was too weak to find its way back out of the river on its own, died despite rescuers’ attempts to transport it back to sea.

In 2009, a humpback whale was found washed up on the shore of the Thames in Kent having seemingly died from starvation.