Harvest Mouse – Micromys minutus
Breeding nests are the most obvious sign indicating the presence of harvest mice. The harvest mouse is the only British mammal to build nests of woven grass well above ground. Nests tend to be found in dense vegetation such as grasses, rushes, cereals, grassy hedgerows, ditches and brambles. They are generally located on the stalk zone of grasses, at least 30cm above ground in short grasses and up to a metre in tall reeds. The size of the nest can vary from only 5cm in diameter for non-breeding nests to 10cm in diameter for breeding nests.
Harvest mice have many predators: weasels, stoats, foxes, cats, owls, hawks, crows, even pheasants.
Very small size weighing only 6g when adult. Fur is sandy brown colour with paler underside. Has blunt muzzle, small eyes and small hairy ears. The prehensile (capable of grasping) tail is the same length as the head and body. Only 5-7cm long.
Hazel Dormouse (Muscardinus avellanarius)
Much larger than harvest mouse. Orange/yellow coat on top with yellow underside and white on throat, unlike golden-brown colour of harvest mouse, which also has a very pale grey/white underside. Prominent, big black eyes, whereas harvest mouse has small eyes. Medium sized ears, more prominent than those of harvest mouse. Furry tail. Harvest mouse tail is much less furry.
House Mouse (Mus domesticus)
Much larger than harvest mouse. Grey/brown fur, unlike golden-brown of harvest mouse. Much more prominent ears than small subtle ears of harvest mouse and bigger eyes. Greasy fur, strong smell.
Wood Mouse (Apodemus sylvaticus)
Much larger than harvest mouse. Red/brown on top, darker than golden-brown of harvest mouse. Large eyes and ears, compared to small eyes and small subtle ears of harvest mouse. If you get a closer look: black fur on top of tail that is not present in harvest mouse. Wood mouse has white underside with longitudinal yellow/orange streak between forelegs.
Yellow-necked Mouse (Apodemus flavicollis)
Much larger than harvest mouse. Red/brown on top, darker than golden-brown of harvest mouse. Large, prominent eyes and ears, compared to small eyes and small subtle ears of harvest mouse. If you get a closer look: black fur on top of tail, not present in harvest mouse. Yellow-necked mouse has an unbroken yellow band across neck, joining forelegs.