Changes

Voles are rodents, in the same family (''Crecetidae'') as [[lemming]]s, and like lemmings they sometimes have population explosions. The field vole, ''Arvicola agrestis'', was so plentiful in [[Scotland]], causing so much damage in 1890-1 that the Government appointed a Committee to examine the question. The committee wondered whether the destruction of predators by gamekeepers was responsible, but in true [[Darwin]]ian fashion, the Scottish outbreak was dealt with by a rapid natural increase in the population of [[birds of prey]].<ref>http://www.electricscotland.com/books/wildlife6.htm</ref> A more recent vole explosion permitted [[snowy owl]]s to colonise and breed in the [[Shetland]] Islands for a number of years.

Voles are rodents, in the same family (''Crecetidae'') as [[lemming]]s, and like lemmings they sometimes have population explosions. The field vole, ''Arvicola agrestis'', was so plentiful in [[Scotland]], causing so much damage in 1890-1 that the Government appointed a Committee to examine the question. The committee wondered whether the destruction of predators by gamekeepers was responsible, but in true [[Darwin]]ian fashion, the Scottish outbreak was dealt with by a rapid natural increase in the population of [[birds of prey]].<ref>http://www.electricscotland.com/books/wildlife6.htm</ref> A more recent vole explosion permitted [[snowy owl]]s to colonise and breed in the [[Shetland]] Islands for a number of years.

Voles range in color from gray to brown and in size from three to nine inches long. They have rounded bodies and blunt snouts, small ears and short tails without much hair. Their main food is grasses, but they also eat bark, leaves and insects. There are about 70 species, 40 of which (found in [[North America]], [[Eurasia]] and [[North Africa]]) are in the genus ''Microtus'', which usually make shallow burrows or runways under vegetation. Confusingly, these are called [[field mice]] in North America (in the rest of the world, field mice are a completely different animal). The five species in the genus ''Clethrionomys'' nest in shrubs, and those in the North American genus ''Phenacomys'' nest in trees and are called tree mice. The ''Lagarus'' species found in the western US is called the sagebrush vole, while that found in [[Russia]] and [[Mongolia]] is misleadingly called the steppe lemming. Voles also are known to strip the bark in a circle around fruit tree trunks, which often kills the tree. They tend not to like human houses, though they sometimes infest barns.<ref>http://www.bbc.co.uk/nature/wildfacts/factfiles/268.shtm</ref><ref>http://www.terminix.com</ref><ref>http://www.the-aps.org/press/conference/steamboat/1.htm</ref>

Voles range in color from gray to brown and in size from three to nine inches long. They have rounded bodies and blunt snouts, small ears and short tails without much hair. Their main food is grasses, but they also eat bark, leaves and insects. There are about 70 species, 40 of which (found in [[North America]], [[Eurasia]] and [[North Africa]]) are in the genus ''Microtus'', which usually make shallow burrows or runways under vegetation. Confusingly, these are called [[field mice]] in North America (in the rest of the world, field mice are a completely different animal). The five species in the genus ''Clethrionomys'' nest in shrubs, and those in the North American genus ''Phenacomys'' nest in trees and are called tree mice. The ''Lagarus'' species found in the western US is called the sagebrush vole, while that found in [[Russia]] and [[Mongolia]] is misleadingly called the steppe lemming. Voles also are known to strip the bark in a circle around fruit tree trunks, which often kills the tree. They tend not to like human houses, though they sometimes infest barns.<ref>https://www.bbc.co.uk/nature/wildfacts/factfiles/268.shtm</ref><ref>http://www.terminix.com</ref><ref>http://www.the-aps.org/press/conference/steamboat/1.htm</ref>

In Europe and Western Asia, the water vole ''Arvicola amphibus'', lives near ditches, streams and rivers. It is the largest British vole, and often mistaken for a rat – in fact Ratty in Kenneth Grahame’s book ''[[The Wind in the Willows]]'' was actually a water vole, making his nest by burrowing into the river bank. Water voles are not quite as well adapted for life on the water as animals like otters and beavers, so his habit of ‘messing about in boats’ was probably a good one. When alarmed, they make a characteristic ‘plop’ as they drop into the water.<ref>http://www.bbc.co.uk/nature/animals/features/289feature3.shtml</ref>

In Europe and Western Asia, the water vole ''Arvicola amphibus'', lives near ditches, streams and rivers. It is the largest British vole, and often mistaken for a rat – in fact Ratty in Kenneth Grahame’s book ''[[The Wind in the Willows]]'' was actually a water vole, making his nest by burrowing into the river bank. Water voles are not quite as well adapted for life on the water as animals like otters and beavers, so his habit of ‘messing about in boats’ was probably a good one. When alarmed, they make a characteristic ‘plop’ as they drop into the water.<ref>https://www.bbc.co.uk/nature/animals/features/289feature3.shtml</ref>

Female water voles give birth to around six young after a gestation period of 20–23 days. The young leave their mother after about 22 days, when she has her next litter. They produce up to five litters from April to September. Despite all this reproductive activity, water vole numbers in the UK have dropped up to 90% in recent years despite their legally-protected status, because of predation from American [[mink]] that have escaped from fur farms, and changes in farming and flood control – a much bigger threat to Ratty than the [[Weasel]]s were. On the principle of ‘the enemy of my enemy is my friend’, the water vole’s new best friend is the [[otter]]. Because of pesticide use, the otter population began to decline 50 years ago. However, the recent revival in the otter population is helping the voles because otters have been keeping mink under control.<ref>http://news.bbc.co.uk/1/hi/uk/5331740.stm</ref>

Female water voles give birth to around six young after a gestation period of 20–23 days. The young leave their mother after about 22 days, when she has her next litter. They produce up to five litters from April to September. Despite all this reproductive activity, water vole numbers in the UK have dropped up to 90% in recent years despite their legally-protected status, because of predation from American [[mink]] that have escaped from fur farms, and changes in farming and flood control – a much bigger threat to Ratty than the [[Weasel]]s were. On the principle of ‘the enemy of my enemy is my friend’, the water vole’s new best friend is the [[otter]]. Because of pesticide use, the otter population began to decline 50 years ago. However, the recent revival in the otter population is helping the voles because otters have been keeping mink under control.<ref>http://news.bbc.co.uk/1/hi/uk/5331740.stm</ref>

Water voles like to use a latrine for excretion, and their droppings - cylindrical with blunt ends – are often piled up together near their burrows, which often have grazed areas around the entrance.<ref>http://www.bbc.co.uk/nature/wildfacts/factfiles/268.shtml</ref>

Water voles like to use a latrine for excretion, and their droppings - cylindrical with blunt ends – are often piled up together near their burrows, which often have grazed areas around the entrance.<ref>https://www.bbc.co.uk/nature/wildfacts/factfiles/268.shtml</ref>

Other plans to help water voles by controlling mink include ‘rafts’ made out of wood, polystyrene, oasis and clay, designed to get the mink to climb aboard and leave footprints, alerting watchers to set traps for them.<ref>http://news.bbc.co.uk/1/hi/wales/north_west/6211208.stm</ref> Protective measures include building culverts to allow them to cross underneath roads safely – Durham Wildlife Trust has a ‘Coals to Voles’ project that aims to protect vole habitat in former coalfield areas.<ref>http://news.bbc.co.uk/1/hi/england/tyne/5178284.stm</ref> In Nottinghamshire, Severn Trent water company bred baby water voles and released them into protected pools at the Kirkby in Ashfield sewage treatment site, microchipping them first in order to monitor their weight and health.<ref>http://news.bbc.co.uk/1/hi/england/nottinghamshire/3799063.stm</ref>

Other plans to help water voles by controlling mink include ‘rafts’ made out of wood, polystyrene, oasis and clay, designed to get the mink to climb aboard and leave footprints, alerting watchers to set traps for them.<ref>http://news.bbc.co.uk/1/hi/wales/north_west/6211208.stm</ref> Protective measures include building culverts to allow them to cross underneath roads safely – Durham Wildlife Trust has a ‘Coals to Voles’ project that aims to protect vole habitat in former coalfield areas.<ref>http://news.bbc.co.uk/1/hi/england/tyne/5178284.stm</ref> In Nottinghamshire, Severn Trent water company bred baby water voles and released them into protected pools at the Kirkby in Ashfield sewage treatment site, microchipping them first in order to monitor their weight and health.<ref>http://news.bbc.co.uk/1/hi/england/nottinghamshire/3799063.stm</ref>