Almost 4,000 seals live at the River Thames’ mouth, located on the southeast coast of England. Zoologists conducted their census in summer 2021. The river has been shown to be cleaner, thus providing better conditions for these pinnipeds and other animals’ population growth.

Monitoring Seals, Promising Results

Using ships and planes, scientists from the London Zoological Society (ZSL) monitored the coast between the English cities of Deal and Felixstowe. The census of animals took place in August when it is the time of molting – seals change their fur and spend a large part of the day on the shore.

Thea Cox monitoring seals. Photo source: ZSL

Biologists have counted and estimated the number: almost three thousand fur seals and about eight hundred common seals. Hundreds of seals lying on the banks and beaches of the Thames estuary, according to experts, are proof that the river flowing through London is significantly cleaner than before. According to biologists, the number of seals suggests that the Thames is a vital ecological hotspot for these species.

The River Thames Back to Life

“It’s really fantastic news for the Thames. It really proves the renewal that the estuary has undergone. We have come a long way since the 1950s, “said Thea Cox, a biologist from ZSL. The Thames was so polluted in the 1950s that scientists declared it biologically dead.

Seals breed in summer. Photo source: ZSL

The Thames provides a home to several other amazing species, short-snouted seahorse, Dover sole, or European eel. The ZSL team actively monitors and supports many of them. Keeping the river water clean is essential for the conservation of these animals.

Around 40% of the fur seal world population lives in Britain. An earless seal is more widespread, their population is estimated at 400 to 500 thousand in the world, about 33,000 of them live in Britain.

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