Synaptomys cooperi Baird
Color photo by Barbara L. Clauson and Robert M. Timm.
Copyright 1999. All rights reserved.
| Southern Bog Lemming
Synaptomys cooperi Baird
Color photo by Barbara L. Clauson and Robert M. Timm. | |
Description: The southern bog lemming can be distinguished from other members of its family by: 1) thick-set body and large head, 2) tail no longer than the hind foot, 3) short ears concealed by its hair, 4) long loose brownish to golden dorsal fur mixed with gray and black hairs, 5) underparts and shoulders washed with white, with slate colored hairs showing through, 6) grayish tan feet with the first digit having a flat nail, and 7) yellowish-orange upper incisors with a groove on the outer edge of the anterior surface. The hip glands of males are similar to those of arctic lemmings in that they have whitish hairs in the pelage covering the glands; the glands are especially conspicuous during the breeding season. Young southern bog lemmings are darker and more slaty than adults.
Size: Adults may attain the following dimensions: total length 122-154 mm; tail 17-25 mm; hind foot 17-26 mm; ear 10-14 mm; weight 39-54 grams.
Range and Habitat: Two subspecies occur in Kansas, Synaptomys cooperi gossi in the eastern half of the state, and Synaptomys cooperi paludis in a small area in the southwestern part of the state. Southern bog lemmings are colonial and inhabit communities of thick matted ground cover with high overhead vegetation in both forest and grassland, but are not restricted to bogs. Vegetation surrounding springs, damp to wet grasslands, and marshes are their favored habitat. From such areas they move out into upland grasslands and other surrounding communities.
Reproduction: After 21 to 23 days of gestation, one to seven (usually three) young southern bog lemmings are born hairless with their eyes closed. On the fifth day their hair appears and in twelve days their eyes open. Three or four litters are produced each year. Females have six nipples. Young born early in the spring may or may not live through the winter, whereas those born in autumn have a favorable chance of surviving through the winter and into the next year.
Habits: The home range of the southern bog lemming is limited. Large greenish fecal droppings and copious cuttings of grass stems are a good sign of the presence of this small mammal. It is active both summer and winter, and in areas of dense overhead cover is frequently active during the day. Runways of the southern bog lemming may be shared with the prairie vole. Their nests are approximately 200 mm in diameter, are made of grasses and weeds, are lined with fine grasses and plant fibers (sometimes with soft fur), and are placed in tunnels 100-150 mm below ground, under logs, or above ground among bunches of grass generally nests are built above ground in summer and below ground in winter.
Food: Food of the southern bog lemming consists of stalks and blades of green grasses, and rarely, invertebrates.
Remarks: The southern bog lemming is preyed upon snakes, hawks, owls, weasels, foxes, coyotes, and bobcats. Average longevity for this mammal is less than one year. The Kansas Department of Wildlife & Parks lists southern bog lemmings as a species in need of conservation.