Harvest Mouse Project

The Harvest mouse is Britain’s smallest rodent, barely weighing as much as a 2p coin. It is also highly secretive and very few people are lucky enough to see one in the wild. The summer breeding nest consists of a ball of shredded grass woven around several taller stalks and is thankfully far easier to find.

We knew very little about the Harvest mouse in Surrey - how widespread it was or how many there might be, for example. So we designed and ran the Harvest Mouse Project for four years, initially part-funded by the People’s Trust for Endangered Species. Intensive study on a number of Surrey Wildlife Trust nature reserves in the valley of the River Wey has turned up various hotspots where healthy populations are thriving.

Because they are so small and light, trapping was notoriously difficult. Our project trialled various new methods of detection and combined these with proven techniques such as nest-searching during the autumn and winter.

If you are interested in helping us and want to be trained to find Harvest mice where you live, please do get in touch.

Register as a volunteer >>