Sharks, seahorses, eels and seals have been found living in the River Thames, a study has found.
The State of the Thames Report, led by the Zoological Society of London (ZSL), highlights changes since the river was declared “biologically dead” in 1957.
The river has seen an increase in its range of birds, marine mammals and natural habitats since the 1990s.
However, a number of fish species found in the tidal areas of the Thames have showed a slight decline, experts found.
Conservation scientists said further research was needed to determine the cause.
Climate change has increased the temperature of London’s waterway by 0.2C a year, the study said. The rising temperature has meant water levels in the tidal Thames have increased since 1911, ZSL said.