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Project LeaderZoological Society of London (ZSL) Project PartnersFriends of the River Crane Environment (FORCE)London Wildlife Trust Funding SourcesEsmee Fairbairn FoundationProject BudgetUnknownProject Timescale2011 - 2013

European Eel Project

ZSL trained volunteers, supported by LWT, have been monitoring upstream eel movement on the River Crane, at the Crane Park Island Nature Reserve, since 2011. We have not recorded any elvers traveling upstream in that time. This contrasts with the 14 other sites in the Thames catchment where we record elvers albeit in small numbers at some sites.

The project provides evidence that barriers downstream of the trap site are stopping natural eel recruitment into the river. In 2012 we surveyed the barriers in the lower stretch of the River Crane and DNR. The issue of eel passage on the downstream reach of the River Crane past Mereway Weir to the River Thames is superseded by a more pressing need to restore and rehabilitate the general ecology of this stretch of river. There are multiple barriers to eel migration on this very impoverished stretch. Adding eel passes at Kidds Mill Sluice and over a small barrier at Mogden Sewage works, both on the DNR, however will allow eels to enter the Crane catchment. 

The eel monitoring will finish at the end of 2013 at Crane Park Island, but ZSL will continue working with the CVP to improve the Crane catchment and, in particular, work towards natural eel recruitment into the river. In 2015 Statutory measures will come into effect to help eel populations across Europe. The European Council Regulation No 1100/2007 will mean that owners of barriers such as weirs, that restrict eel movement, will be obliged to install eel passes.

Once passes are added to Kidds Mill Sluice and Mogden sewage works our intention is to reinstate the eel monitoring programme to check elvers are entering the river. Further project information and reports are available from