A PROJECT to reintroduce harvest mice to part of the region is gathering pace.

The scheme is backed by Chester Zoo and Stockton Borough Council, whose area includes the planned release site, at Castle Eden Walkway.

Harvest mice are still widely distributed in southern England, but agriculture and development of the countryside has robbed the creature of many nest sites in the region.

Naturalists believe there are only five remaining colonies in the North-East, all in rural Northumberland.

Stockton council countryside warden Ian Bond, the project co-ordinator in the North-East, said plans for the release at Castle Eden were well advanced.

He said: "We now have approaching 150 mice spread among about 30 volunteers throughout the North-East. The number has started to increase fairly rapidly, as several pairs are now breeding."

Mr Bond said the first batch would be released in June, to coincide with the increase in insect populations on which harvest mice feed during the summer.

The animals will be kept in wire pens before release to get used to the area, which previously supported the animals before they died out.

Mice will also be released on to a farm in Northumberland and studied by Wendy Fail, a student from Newcastle University who is doing a PhD on harvest mice.

She will monitor their progress to assess the viability of introducing the animal to more sites in the county.

Mr Bond and fellow naturalists are gathering information on other possible release sites in the region.

The latest update is reported in the newsletter of the Northumbrian Mammal Group, of which Darlington man Mr Bond is the editor.