Bank Vole (Myodes glareolus)
- Voles live all over the grassland on Cowbar and in the banks alongside the Cleveland Way. They tunnel under the mats of grass on the cliff top and the tiny entrances to their burrows are easy to spot everywhere.
- We think it is mainly bank voles which have been visiting the mammal feeding boxes this summer. However, field voles do look very similar and the species’ types of preferred habitats often overlap.
- The field vole ( Microtus agrestis), sometimes known as the ‘short tailed vole’ has a population of 75 million in the UK bank voles (approx. 23 million) so it’s likely we have both species living on Cowbar. It’s probably their runs and burrows we uncovered in the grassland while clearing space for yellow rattle.
- The main difference is that a bank vole has a more reddish-brown fur while the field voles tend to be more grey-brown. Since a lot of our trail camera footage of voles is taken in the night, this still leaves some uncertainty but some of the daylight photos seem to show the reddish-brown coat and paler underbelly of the bank vole. The cameras are closer to ‘hedgerow’ type territory that bank voles prefer.
- The other difference is that a bank vole’s tail is about 50% of its total body length whereas the field vole’s is shorter at 30%. Bank voles have large ears, but not as large as mice.
- Bank voles are more agile than field voles who are not great climbers. Since the mammal boxes have a raised entrance, this also suggests we have been filming the more agile bank voles.
- They are active during day and night and forage over distances up to 50 metres.
- They make their nests in shallow burrows which they line with leaves, moss, grass and feathers.
- Both types of voles are an extremely important part of the diet of many predators such as kestrels, weasels, foxes and barn owls and we know we have all of these living on Cowbar.
- Bank voles do not hibernate and have 3 to 4 litters a year, each with 3 to 5 young. These are born between April and October.
- Voles are born hairless and blind but are weaned after about 25 days and the females are ready to mate after 6 weeks (and the males in 8 weeks).
- They eat seeds, nuts, fungi and insects and are especially keen on blackberries and hazelnuts.
- Bank voles can live for up to two years but they have so many predators that this is unusual.
- They have no legal protection or conservation status in the UK but their numbers can be threatened by habitat loss and pesticides.
