Mammals of Coombe Bissett Down: small mammals Small mammals The mammals most responsible for draining batteries and filling memory cards were mice. Over the two months, the trail camera compiled a seemingly endless montage of these tiny animals, scurrying around in the entrances to badger setts and fox dens, gorging themselves on seeds, and collecting bits of material to stuff into their burrows. After a lot of deliberation, I am confident that I collected footage of two species across the reserve: wood mice (Apodemus sylvaticus) and yellow-necked mice (Apodemus flavicollis). The latter of the two is actually rather rare as it is a specialist of tree seeds – making it a key indicator of good habitat quality – and it is only found in mature deciduous woodland in the southern half of Britain. Wood mice, however, are very common and can be found in gardens, moorlands, wetlands, arable fields, and even road verges, despite its name. I also found uneaten carcasses of common shrews (Sorex araneus) on the reserve, which is a surprisingly common occurrence as they are distasteful to most predators and are usually left alone as a result. During autumn, wood mice collect extra bedding material and cache berries and seeds in their burrows in preparation for winter. Mice do not hibernate, but they do nest communally to keep warm and will often block up entrances to their burrows. Females may even breed over winter if there is enough food. Like in badgers, allo-grooming in mice reinforces social bonds and cleans areas that are difficult to reach, but it is also used to convey information about sources of food and the quality of potential mates. This clip is of two yellow-necked mice – they have slightly larger ears, a longer tail, and more bulging eyes than wood mice, and have a more hopping, kangaroo-like run.