More news...

Jul 6, 2018
Category: Drought
Posted by: Kathryn

With this hot weather our water use goes up; this leaves less water available for the Chess.

May 3, 2018
Category: Abstraction
Posted by: Kathryn

With an ever-growing demand for drinking water and increasingly extreme weather events, how do we get the water we need without causing even more harm to our rivers?

May 2, 2018
Category: Drought
Posted by: Kathryn

Our riverfly monitors are back out in the centre of Chesham checking for life in the Chess now that flow has returned.

Mar 24, 2018
Category: HS2
Posted by: Kathryn

A public meeting with HS2 and the Environment Agency looked at the risks posed by tunnelling to the groundwater and rivers of the Chess and Misbourne Valleys.

Latest News

Water Voles Need Our Help

Mar 13, 2016

Category: Water Voles
Posted by: Kathryn

The 2015 survey of the River Chess water voles revealed a 46% population decline since 2013. It is estimated that there are 127 water voles now living on the Chess. This decline may in part be due to natural fluctuations in numbers, but there is evidence to show that the invasive, predatory mink are once again threatening the vole population.

Water Vole Surveyor in the Chess

A water vole surveyor on the Chess in 2015

The Chess nearly lost its water vole population in 2003, when mink dispersing along the watercourse caused a 97% population decline. In 2004, a mink control scheme was initiated enabling the water vole population to fully recover by 2011. In October 2015, signs of mink were recorded on the upper Chess once again, helping to explain the poor results of the survey that had been carried out over the summer. In December 2015, mink prints were detected on a mink raft at Latimer and an adult mink was subsequently trapped.

The return of mink to the river caused the Chiltern Chalks Streams Project and BBOWT to carry out an audit of mink rafts that had been placed on the river with landowners between July 2014 and June 2015. Of the 17 rafts in place, only three were still in use and being regularly monitored, explaining how mink had returned to the river without being detected. The RCA, BBOWT, Chilterns Chalk Streams Project and the Herts & Middlesex Wildlife Trust met this week to organise setting up routine monitoring of mink rafts along the entire length of the Chess, from Chesham all the way down to Rickmansworth. This will involve placing new rafts at strategic points along the river, with landowner permission, and engaging volunteers to check the rafts on a regular basis. It is key that the new rafts are in place in time for Autumn, when mink start to travel more widely.

In the mean time, we would ask anyone who sees a mink, or signs of mink, in the Chess Valley to let us know.

The 2015 water vole survey was led by the RCA with support from the Chilterns Chalk Streams Project and BBOWT. We would like to thank all the volunteers who carried out this vital work, and the landowners who generously allowed us to survey their land.