The Skomer vole is a unique sub-species of bank vole which is endemic to Skomer Island off the Pembrokeshire coast.
Last updated: 24 May 2011
Quite how the voles arrived on Skomer Island is still a mystery as the island is cut off from the mainland by a dangerous stretch of water known as 'Jack Sound' but it is likely that they arrived via a boat delivering supplies at some point in the past.
Horses and livestock were once swum over to the island too and a family once lived and farmed on the island, finally selling up in 1950.
In the summer months, there are approximately 20,000 voles on the island but most visitors are completely unaware of their presence as they're too busy watching the colourful puffins and assorted sea birds nesting.
The voles favour the bracken rich slopes and longer grasses which provide plenty of shelter where they remain relatively safe as there are no land based predators on the island.
Other rodents on the island include rabbit, long-tailed field mice, pygmy shrew, common shrew and vole. The grasses on the island have adapted accordingly in order to survive so the Red Fescue and Common Bent thrive as they are fairly inedible to rodents and as such, grow to a good height.
The voles however play an important part in the island's ecology and provide a staple diet for the island's owl population which consists of short-eared, little and barn owl, all of which can often be spotted hunting during the daylight hours.
Other birds of prey on the island relying on the voles as a food source are kestrels, buzzards and the occasional peregrine.
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