Harvest Mouse on Hazeley Heath

Recently a small mammal survey was conducted on Hazeley Heath to ascertain what we have both living on the heath itself and the rough grassland as a mammal survey has never been done before here. Hampshire and Isle of Wight Wildlife Trust set up 80 longworth traps, baiting them with cereal grains, carrot, casters and hay bedding over the course of three days. When a mammal was discovered the traps were carefully emptied into survey bags and the age and species of each small mammal found was recorded.

No small mammals were found on the heathland, though we suspect that we just did not succeed in trapping any on this occasion. Three species of mammal were found on the grassland and 15 animals were found in total. Woodmice were the most prevalent species found, reflecting national population trends. A Field vole was also found but the most exciting find was that of a Harvest Mouse, as they are believed to be declining nationally and are listed as a UK Biodiversity Action Plan Species.

The Harvest mouse, Micromys minutes, is Britain’s smallest rodent and the only Old World mammals to have truly prehensile tails. They have yellow/brown fur, with a white underside, a blunt muzzle and small hairy ears. Harvest mice inhabit hedgerows, reedbeds, and other areas of tall, dense vegetation, such as can be found on Hazeley. They feed mainly on seeds, fruits and bulbs, but a tiny proportion of their diet is made up of insects, particularly in the summer, as well as roots, moss and fungi. Some food is cached underground for the winter. Spherical nests are made from woven grass and are built in stems high above the ground. (Picture taken by Deborah Whitfield).

We are very excited to have confirmation of the presence of these rodents on Hazeley Heath. There has been a 71% decline in their numbers over the past 18 years because they are vulnerable to impacts of landscape change, habitat loss and fragmentation. Place of particular importance are field margins, wet habitats and hedgerows as refugia.