Mystery of vanishing eels
January 21st, 2010 | by lucy |
The eel population of the Thames has dropped by 98% in 5 years and conservationists can only speculate why. The Thames eels (Anguilla anguilla) are born 4000 miles away in the Sargasso Sea, located in the North Atlantic Ocean, from where they migrate to British fresh waters. After up to 20 years they return to their breeding grounds to spawn and die. To make these long journeys the eels rely on ocean currents, which are susceptible to changes in temperature.
Disease and pollution could also be causing problems for the eel. Although the Thames has revived since its “biological death” in the 1950s, the river remains under heavy urban pressure. And the Sargasso Sea, in contrast with its romantic image, suffers from a particularly high concentration of non-biodegradable plastic waste, trapped there by ocean currents.
Fears about the impact of last December’s severe weather, the coldest in 100 years, were unfounded. The drop in small bird populations witnessed in the 
The oldest osprey of the UK – and probably the world – has returned to her eyrie in the Scottish highlands. When she left for West Africa at the end of last summer, no one expected her to return. At 26 she’s lived 3 times longer than most female ospreys. In her life she’s laid 58 eggs and hatched 48 chicks, a massive individual contribution to the survival of ospreys in Scotland, where there are still only about 200 breeding pairs. The questions now are if her mate will return and if she is still fertile. Events can be followed on the 
The construction company currently finishing off the Shard building in London, which will be the UK’s tallest skyscraper, recently had to call the council to remove a squatter from the 72nd floor: a young fox. He was surviving on scraps left by builders. After a check-up at the Riverside Animal Centre, the fox has been released on the streets of Bermondsey, having shown the type of curiosity we associate with cats. 
Otters, water voles and fish are all benefitting from the improved quality of the UK’s waterways, now described as the cleanest since the industrial revolution. Since almost disappearing from the wild in the 1970s, otters are thriving, particularly in the south west of England, Cumbria and Northumberland. The population of water voles, highly precarious in the 1990s, is also beginning to recover. The good results of stricter pollution controls and extensive conservation work are set to continue in the new year with the introduction of new European water quality directives. 
