Seahorses Discovered in England’s River Thames

Clean-up leading to improved water quality benefits Hippocampus hippocampus

An amazing discovery has just been made in the heart of London by the Environment Agency, which monitors wildlife populations in England. Its scientists have found evidence of a colony of seahorses in the River Thames which flows right through the city, during a routine fisheries survey at Greenwich. This is the first time that these rare creatures have been found so far up the Thames and the first time ever in this part of London.
Occurring in Temperate and Tropical Waters
Although it is often assumed these fish are confined to tropical seas, seahorses have always been visitors to the coastal waters around the British Isles. Recent sightings suggest that there may be more permanent populations in areas around the UK and during 2008, they became fully protected under domestic wildlife legislation.

Prior to this change in the law, a small number of individuals had previously been found in the River Thames. This raised the possibility that the river could be supporting a colony, but none had been found since then, until now, and they have never been recorded this far inland from the sea.
The species which has been discovered, the short-snouted seahorse (Hippocampus hippocampus), can grow up to around 6in (15cm). It is relatively rare in the UK, mainly being found along the south coast.
Regular Monitoring
The Environment Agency has carried out regular monitoring of the fish populations within the Thames Estuary since the late 1980s. This data has enabled scientists to gain a better understanding of the importance of the river as a nursery and breeding ground for a number of species of commercial and conservation importance. Seahorses themselves are one of the few fish that mate for life after elaborate courtship rituals.

Emma Barton, Environment Agency Fisheries Officer said “The seahorse we found was only 2in (5cm) long, a juvenile, suggesting that they may be breeding nearby. This is a really good sign that seahorse populations are not only increasing, but spreading to locations where they haven’t been seen before. We routinely survey the Thames at this time of year and this is a really exciting discovery.
“We hope that further improvements to water quality and habitat in the Thames will encourage more of these rare species to take up residence in the river. The young seahorse itself was released back here, and will hopefully breed in due course.”

Article Categories:
Fish · Freshwater Fish