The water vole (Microtus richardsoni ) is the largest North American vole. It is found in the northwestern United States and southern parts of western Canada. This animal has been historically considered a member of genus Arvicola, but molecular evidence demonstrates that it is more closely related to North American Microtus species. Water voles are on the USDA Forest Service Region 2 sensitive species list because they maintain very small populations and there is high concern that their required habitat may be declining.
These animals have gray-brown or red-brown fur with gray under parts. Their large hind feet help make them excellent swimmers, and they are found in alpine or semi-alpine meadows near water. They feed on grasses, leaves, roots and seeds, also eating small invertebrates. Water voles dig burrows that are connected to water sources, and are considered a semi-aquatic species.
They are active year-round, tunneling through snow during the winter. Their burrows often have entrances at the water's edge or under water, and they usually live in colonies of 8-40 individuals along the waterway.
The word vole originated in approximately 1805, and is short for vole-mouse, which means field mouse. Vole originated from the Norwegian word vollmus; voll, meaning field, and mus, meaning mouse. It is also possible that there were influences from Swedish vall, which translates to mean field.
Microtus richardsoni is also known as Richardson's water vole, Richardson vole, Richardson's meadow vole, Richardson meadow mouse, water rat, big-footed mouse, giant water vole, and water vole.
Te
TerrestrialTerrestrial animals are animals that live predominantly or entirely on land (e.g., cats, ants, snails), as compared with aquatic animals, which liv...
Among animals, viviparity is the development of the embryo inside the body of the parent. The term 'viviparity' and its adjective form 'viviparous'...
A burrow is a hole or tunnel excavated into the ground by an animal to create a space suitable for habitation, temporary refuge, or as a byproduct ...
A fossorial animal is one adapted to digging which lives primarily but not solely, underground. Some examples are badgers, naked mole-rats, clams, ...
Semiaquatic animals are those that are primarily or partly terrestrial but that spend a large amount of time swimming or otherwise occupied in wate...
Polygyny is a mating system in which one male lives and mates with multiple females but each female only mates with a single male.
W
starts withWater voles have unusually large hind feet, ranging between 25 and 34 mm in length, which can help distinguish the water vole from other similar rodents, and contribute to its speed in the water. Males tend to be larger than females. On average these animals are about 20–27 cm in total length (including the tail), with tails 6–10 cm long, and weigh 125-178 grams. The water vole is the second largest arvicoline in its range (after the muskrat).Their fur is grey-brown, dark brown, or reddish-brown on the upperparts, and is grayish-white on their underside. The water vole's large incisors, combined with its very large skull and well developed zygomatic arch (which strong chewing muscles attach to), contribute to its ability to efficiently dig tunnels and chew through tough roots.
Water voles live in two distinct bands through the western United States and Canada, extending from British Columbia and Alberta through parts of Oregon, Washington, Montana, Idaho, Wyoming, and Utah. They are found in alpine or semi-alpine meadows near water, usually between 914-3,201 m in elevation. The distribution of habitats is found to be extremely variable, due to the geographical barriers of large coniferous forests, mountains, and expansive valleys without readily available waterways. Although, genetic data has been collected that suggests water voles do have the ability to disperse over land to reproduce with other populations, this overland dispersal between colonies tends to be higher with adjacent populations, and less so with increased distance. Because water voles live in such small isolated patches it is necessary for them to form such a metapopulation structure, in which dispersal can balance out local extinction.
Their main source of food is vegetation, including leaves, stems, grasses, sedges, willows, and sometimes seeds or insects. Their food source varies significantly depending on geographic location. Studies have shown that water voles have a very high metabolic rate, and therefore don't have to consume as much food as other rodents their size. Most often, water voles feed on the subterranean portion of plants, which are available to them year round. There is no evidence that they store food for the winter. During the winter they are seen to dig tunnels through the snow, and usually do not surface above the snow once 6 cm have accumulated (approx. 7 to 8 months of the year). Water voles are most active at night, and they travel between tunnels, nests and waterways by means of surface runways 5–7 cm wide through the vegetation. Often tunnel or burrow entrances are found either at water level or submerged along the river banks. They construct these tunnels and nests just below the roots of the vegetation (about 4–6 cm below ground) during the breeding season (June through late September). Females give birth and care for her young in these underground nests, lined with leaves and grass.
Social animals are those animals that interact highly with other animals, usually of their own species (conspecifics), to the point of having a rec...