Sharks, seahorses and seals have been found living in the 215-mile long River Thames that runs through London, a study has found.
The State of the Thames Report, led by the Zoological Society of London (ZSL), highlights that the famous river which was declared "biologically dead" in 1957 has shown a marked improvement since then with an increase in its range of birds and marine life.
The report said shark species including tope, starry smooth hound and spurdog live in the Thames and there are more than 100 species of fish in the 215-mile long river. There are also as many as 92 bird species.
However, the number of fish have declined since the 1990s, and further research is needed to determine the cause, the report also points out.
It states that water quality has improved, with dissolved oxygen concentrations showing an increase from 2007 to 2020.
But nitrates from sewage are getting worse – although that is expected to improve when London’s "super sewer" opens in 2025. The £4.2bn, 15-mile long, 200ft deep sewer will capture 39 million tonnes of untreated sewage that is currently flushed into the Thames every year, according to BBC News.
The report also expresses concern over climate change leading to an increase in the temperature of London's waterway by 0.2C a year. The rising temperature has meant water levels in the tidal Thames have increased since 1911, ZSL said.
The scale of plastic pollution littering the tidal Thames as well as thousands of plastic bottles, wet wipes is another area of concern highlighted in the report.
One mound of wet wipes in Barnes has grown in height by 1.4 metres since 2014 and covers an area of 1,000 sq metres.
“These products, many of which contain plastic, are physically altering the foreshore along the Thames by creating large mounds of sediment densely bound together,” the report adds.