Bush gopher, Franklin ground squirrel, Gray gopher, Gray ground squirrel, Gray souslik, Gray-cheeked squirrel, Grey American marmot, Line-tailed squirrel, Prairie squirrel, Scrub gopher, Spermophile de Franklin, Whistling ground squirrel, Franklin's groun
Franklin's ground squirrel (Poliocitellus franklinii ) is a species of squirrel native to North America, and the only member of the genus Poliocitellus. Due to the destruction of prairie, the populations of Franklin's ground squirrel have dwindled, approaching levels of concern. Its decline in the eastern portion of its range is mostly attributed to habitat fragmentation.
Franklin’s ground squirrel, like others of its genus, is a mainly terrestrial rodent and has a relatively short, furry tail, large cheek pouches in which it carries food, and short legs. Ground squirrels typically use a large range of vocalizations, such as trills, chirps and squeaks. These squirrels are typically more vocal than other types of ground squirrels, making bird-like twitters and clear, musical whistles, which gives them their other name: ‘whistling ground squirrel’.
Franklin’s ground squirrel lives in the central United States and north into Canada. They inhabit the southwest of Ontario across to central Manitoba, south to central North Dakota and through central Kansas. Their range is as far to the east as west-central Indiana, and in the northwest to the shores of Lake Michigan in the Michigan City-Chicago area. These squirrels typically inhabit tall grass prairies, although they are also found in fields, marsh edges, hedgerows, forest-field edges, and along strips of railroad land and roadsides, if these are not mowed.
These squirrels are amongst the least social of their genus, generally living in loose colonies which are hardly ever more than 10 to 12 animals. Its population seems to fluctuate, reaching a peak about every four to six years. They often remain in one area for a brief period before disappearing and establishing a colony somewhere else. These squirrels are diurnal and most active during bright, sunny days. They seem to be above ground for about 10% of their time. They dig burrows that may be as deep as 8 ft underground, with several branches and openings. They build up a thick layer of fat during the late summer to sustain them during hibernation in winter. By late September, every squirrel has chosen an underground spot in which to hibernate. They hibernate through winter and emerge during late March or early in April.
Franklin's ground squirrels are omnivorous, they eat grasses, clovers, dandelion, mustard, thistle, strawberry, and other plants, as well as cultivated crops like wheat, corn, oats, and garden vegetables. They will also eat beetles, caterpillars, crickets, grasshoppers, ants, small birds, ducks, frogs, toads, deer mice, birds' or ducks' eggs, as well as other ground squirrels.
Little is known about the mating system of Franklin’s ground squirrels. However, like their related ground squirrel species, they might be either polygynous (one male mates with multiple females) or polygynandrous (promiscuous) (both males and females have multiple mates). The mating season starts when the squirrels come out of their burrows in spring and is finished by mid-April. Gestation lasts for about 28 days, with young being born in the month of May or June. The Franklin's ground squirrel has one litter each year, numbering 5-10 babies (7 on average). When born the young are blind and naked but after ten days fuzzy hair appears. When they are 20 days old their eyes open and they are able to make whistle calls. At 30 days old they leave the burrow and at 40 days old weaning is completed. When winter arrives, the young are nearly adult size. A young squirrel is not ready for mating until after it has hibernated at the end of its first year.
The main threat to the Franklin’s ground squirrel is thought to be the fragmentation and destruction of tall grass habitats, the result, for example, of urban development and agricultural expansion. These squirrels may also be affected by pesticide poisoning or by poisons used to kill the plains pocket gopher. Road deaths are another threat. The isolation and fragmentation of the squirrel’s populations could potentially prevent sufficient dispersal of these animals and lead to inbreeding.
The IUCN Red List and other sources do not provide the Franklin’s ground squirrel’s total population size. Currently this species is classified as Least Concern (LC), but its numbers are decreasing.
Franklin's ground squirrels disperse the seeds of many plant species. Also, as prey animal, they may have an impact on predator populations, including the red-tailed hawk, red fox, badger, coyote, striped skunk, mink, and long-tailed weasel.