Humpback whales are returning in increasing numbers to UK waters, with 75 views off the Cornish coast alone since 2019.
The animals, famous for their “song,” have also been sighted off the Isles of Scilly, Shetlands and the Firth of Forth, according to the Wildlife Trust’s annual marine review. An individual, nicknamed Pi, lingered in the Scillies for two months.
Sightseeing of whales in British seas had been extremely rare in previous decades, with animals pushed to the brink of extinction by centuries of whaling.
Between 1994 and 2010, observations and seismic surveys confirmed only 48 humpback whales in the UK and adjacent waters.
Figures around the world have rebounded from a 1966 moratorium on whaling, as conservationists believe the species is being drawn to the seas around Britain by exploding populations of small fish, as sardines.
Matt Slater, Marine Conservation Officer for Cornwall Wildlife Trust, said: “Only a few years ago it would have been extremely rare to see a humpback whale in the UK. But it looks like they are hunting the large schools of sardines that are now present around our coasts. It’s wonderful to see these creatures up close.
The upsurge in sardines, however, may not be all good news. The increased availability of food for whales is believed to be linked to the decimation of cod, tuna and shark populations through overfishing. These predators would otherwise feed on the same sardines and other small fish eaten by humpback whales.
Climate change, fisheries and development “have a huge impact on life at sea”
Wildlife trusts across the country have also reported a number of species popping up in usual and sometimes disturbing places.
Orcas which normally reside in the Hebrides were seen off Cornwall, only to return to Scotland within nine days, before reappearing off the coast of Dover, Kent, a fortnight later.
In addition to killer whales, white beaked dolphins have been sighted off the coast of Essex for the first time in over 20 years, while Moray Firth bottlenose dolphins have been recorded on the south coast for the first time. .
At least two walruses have been seen in British waters, while ring-necked blenny and crisscrossed crab have established themselves in Cornish waters.
The Wildlife Trusts have warned that these unusual sightings and changing species are a sign of climate change, which is altering sea temperatures and displacing both prey and predators.
“It has been a fantastic year for marine megafauna sightings, especially in the southwest,” said Lissa Batey, marine conservation manager for The Wildlife Trusts.
“But it is clear that our oceans are under immense pressure from fishing, development, pollution, climate change and recreation. All of these issues have a huge impact on life at sea.”
Humpback whales still under threat, despite resurgence
By the time of the 1966 moratorium, the world’s humpback whale population had declined by 95% from their estimated pre-whaling numbers. Perhaps 10,000 to 15,000 survived. The North Atlantic population has fallen to as few as 700 whales.
By 2020, the global population had fallen to around 80,000 inhabitants. Nonetheless, like all whales, humpback whales still face many threats, including entanglement in fishing gear, collisions with boats, and underwater noise pollution from ships.
Humans have hunted whales for millennia, but by the beginning of the 18th century commercial-scale whaling had started to decrease their numbers and take them away from coastal waters.
The main source of demand was whale oil, which burned cleaner and more vigorously than other fat-based fuels.
In the mid-19th century, the invention of explosive harpoons and steamers led to exponential growth in capture levels and the collapse of whale populations.
Some of the worst damage was done in the mid-20th century, with the Soviet Pacific Fleet illegally killing over 180,000 whales between 1948 and 1973 to meet economically irrational production targets.
In the 20th century alone, scientists believe that nearly three million whales of all species were captured in the oceans.