Southern bog lemmings are found in eastern North America, from southeast Canada to western Minnesota, down to southwest Kansas and east to northeast North Carolina.

Biogeographic Regions: nearctic (Native )

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: Southern Quebec west to southern Manitoba, south to Kansas, northern Arkansas, Tennessee, North Carolina, Virginia, and Maryland.

Southern bog lemmings are small voles, weighing 20 to 50 grams and measuring 110 to 140 mm in total length. The dorsal pelage ranges in color from a chestnut to dark brown that has a grizzled appearance. The venter is silver-gray. Females of this species have 6 mammae, which differentiate it from its closest relative, Synaptomys borealis, which have 8 mammae. The orange incisors are broad and longitudinally grooved. The tail is short, barely longer than the hind foot.

Range mass: 20 to 50 g.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: sexes alike

Length: 15 cm

Weight: 50 grams

• Terrestrial

Synaptomys cooperi occurs mainly in sphagnum bogs, as its common name suggests, but it may also occur in grasslands, and in Canada it occurs in coniferous or deciduous forests. In Michigan, it can be found in clear cuts, old fields, or upland woods. Occurrence within the larger geographic range is patchy--it tends to occupy isolated areas. This is thought to be due to competition with meadow voles.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland ; forest

Wetlands: bog

Comments: Prefers boggy habitat but also common in marshes, meadows, and upland forests with thick humus layer (especially when conditions not hot and dry); areas with intermixture of herbaceous/shrubby vegetation. Occupies burrow systems usually 6-12 inches deep and surface runways (e.g., beneath sphagnum and among roots of shrubs). Young are born in nests placed on the surface in grassy vegetation or in underground burrows. In New Jersey, nests were just under the surface in tops of sphagnum hummocks (Conner 1959).

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Southern bog lemmings eat mostly vegetation such as grasses, sedges, mosses, fruits, fungi, bark and roots. Bog lemmings snip stems near the ground to get access to the upper parts. Often surrounding vegetation prohibits the stems from falling, so additional snips must be made. Some invertebrates such as slugs and snails are also taken. The jaws are powerful and thought to be used extensively for gnawing.

Animal Foods: mollusks

Plant Foods: leaves; roots and tubers; wood, bark, or stems; fruit; bryophytes

Other Foods: fungus

Primary Diet: herbivore (Folivore )

Comments: Diet consists primarily of herbaceous plants; leaves, stems, seeds, and rootstocks, especially of grasses and sedges; also eats small fruits (Conner 1959).

Southern bog lemmings have important ecosystem roles as food for a number of predators (see above) and as competitors with other small rodents, such as meadow voles.

Southern bog lemmings have many predators, including owls, red foxes, gray foxes, domestic dogs, badgers, and house cats.

Known Predators:

• owls
• red foxes
• gray foxes
• domestic dogs
• badgers
• house cats
• owls (Strigidae)
• red foxes (Vulpes vulpes)
• gray foxes (Urocyon cinereoargenteus)
• domestic dogs (Canis lupus familiaris)
• badgers (Taxidea taxus)
• house cats (Felis silvestris)

Home range varies from 1/4 to 1 acre. Densities vary from 5 to 35 per ha, reaching 89/ha in peak years (Banfield 1974). Sometimes occurs on small colonies. Populations usually are scarce and scattered.

There is thought to be intraspecific communication in the form of scent marking from anal secretions. Vocalizations are squeaks.

Communication Channels: acoustic ; chemical

Perception Channels: visual ; acoustic

Comments: Active day and night throughout the year.

Wild southern bog lemmings usually do not live for more than a year. In captivity, they may live up to 29 months.

Range lifespan

Status: captivity: 29 (high) months.

Typical lifespan

Status: wild: 1 (high) years.

Average lifespan

Status: wild: < 1 years.

Average lifespan

Status: captivity: 2.5 years.

Breeding occurs in all seasons, especially where food is not limiting. Most young are born between April and September. Females are polyestrous--one captive bore 6 litters in 22 weeks. Wild females produce 2 or 3 litters per year. Gestation lasts from 23 to 26 days. Mean litter size is 3 but can range from 1 to 8. Males can reach sexual maturity in 5 weeks.

Breeding interval: Southern bog lemmings breed two or three times each year.

Breeding season: Southern bog lemmings breed year round.

Range number of offspring: 1 to 8.

Average number of offspring: 3.

Range gestation period: 23 to 26 days.

Average weaning age: 3 weeks.

Average age at sexual or reproductive maturity (male): 5 weeks.

Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous

Average birth mass: 3.46 g.

Average number of offspring: 3.

Southern bog lemmings weigh 3.7 grams at birth. Young are born with no fur, closed eyes, and with the ear pinnae folded over. Claws are apparent at birth. By the end of the first week, the young are well furred. The female nurses her young for three weeks.

Parental Investment: altricial ; pre-fertilization (Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female)

Breeds year-round; peak April-September. Gestation lasts 21-23 days. Litter size is 1-8 (average 2-5); multiple litters annually in the south. Sexually mature in 60 days, or less for males.

Once very common, numbers seem to be declining as a result of habitat destruction and the overgrowth of bogs. One subspecies, Synaptomys cooperi helaletes, is thought endangered and possibly extinct. Other subspecies also appear to be threatened.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Comments: In Kansas, moved out of or avoided areas subject to experimental prairie fire (Clark and Kaufman 1990). In southeastern Kentucky, apparently being displaced via competitive exclusion by expanding meadow vole populations (Krupa and Haskins 1996).

Comments: Wilson and Choate (1997) examined morphological variation in populations in Arkansas, Iowa, Illinois, Kansas, Missouri, Nebraska, and South Dakota and found that variation was largely clinal, with only minor steps in clinal variation in cranial morphology. Because of small sample sizes, they recommended retention of currently recognized subspecies until genetic data are available.