London Zoo has created a map with all recent sightings of seals and dolphins along the Thames.
Many of these sightings have been reported by ordinary people and if you see seals or dolphins along the Thames you can report them here. If you think seeing a dolphin is a rare thing, you are quite mistaken, dolphins often make their way to central London.
Don’t forget that the River Thames up to Teddington Dock is tidal and also has salt water. Seeing animals such as dolphins and even whales is not a rare thing. As for seals in 2020 alone, 467 seals were sighted and the farthest from the estuary were at Hampton Court. Whales are less common and are often in great trouble when they come to the Thames.