A colony of seahorses has appeared in the Thames River. The short-snouted seahorses were first seen in the river about eighteen months ago, but their presence was kept secret until new laws came into force to protect them from aquarium collectors of exotic fish . Environmental Agency representatives say "We're not quite sure why they're here, but the river water has been clean enough for seahorses for some time." An increase in plankton due to climate change and warmer sea temperatures may be the explanation for the arrival of the seahorses, usually found around Africa and the Mediterranean. Their appearance could be ascribed to better monitoring of the river's species. Others say that it is the result of the loss of more industry along the Thames, thus making the water cleaner.
The river is getting cleaner and cleaner due to environmental regulations being enforced since 1970. At that time the dumping of raw effluent into the water was stopped and tighter regulation on riverside industry was introduced. More than 100 species of fish, dolphins, seals, porpoises and the occasional whale have reappeared over the past decades and is clearly something to celebrate. Recent surveys have found bass, flounder, salmon and Dover sole, as well as the lamprey eel in the river's still murky waters. :: Guardian