WATER voles are being monitored by a group of volunteers who are carrying out a survey in the area.
The group, who have learning disabilities, are carrying out the project at the Royal Gunpowder Mills in Waltham Abbey, with help from the Wildlife Trust.
Water voles have declined in number in recent years, partly due to the introduction of the mink.
Wetlands Awareness Officer for the Wildlife Trust, Alison Hauser said: "The area in and around the Gunpowder Mills has never been surveyed before and we hope to build up an accurate picture of how well the water vole is doing in the area.
"It is also a great opportunity for us to work closely with a team of dedicated volunteers."
The voles are very difficult to spot and so volunteers have created mini rafts and placed them along various parts of the river where the water voles can climb up and activity can be monitored.
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