Yes, you heard that right. Both harbour (common) seals and grey seals have decided that London is a lovely place for a holiday. In 2026, the Zoological Society of London spotted nearly 3,000 of them in the estuary. They pop up as far inland as Teddington Lock, which is basically the suburbs. (Imagine commuting from the North Sea to Richmond just to chill.)
They’re here because the water is actually cleaner than it’s been since the Industrial Revolution. They follow the fish, and the fish are following the cleaner water. It’s a whole, slimy, aquatic chain of life. You’ll see them lounging on buoy platforms like lazy teenagers, flipping their tails at passing boats.
