Eel populations in the river Thames have crashed by 98% in just five years, scientists warned today. The eel, which has been a traditional east London dish for centuries, now appears to be vanishing from the capital's river, according to researchers from the Zoological Society of London (ZSL).
Each year, ZSL's Tidal Thames Conservation Project places eel traps in a number of the river's tributaries, to catch the fish and allow scientists to record numbers before setting them free. While 1,500 were captured in the traps in 2005, just 50 were recorded last year.
The eels are thought to take up to three years migrating as larvae from the Sargasso Sea to European rivers, where they spend up to 20 years before making the 4,000-mile return journey across the Atlantic to spawn and die. But conservationists are concerned the species is not returning to the Thames, or is facing problems in the river and its tributaries.
European eels and flounders were the first species to recolonise the Thames estuary after it was considered "biologically dead" in the 1960s, and there are fears the rapid collapse of the eel population could have knock-on effects for other species in the still-fragile ecosystem.
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http://www.guardian.co.uk/environment/2010/jan/21/eel-thames-population-crash