Franklin’s ground squirrel is active during the day (1) (2) (3), particularly when the weather is bright and sunny (4) (5). Although mainly ground-dwelling, this species is also able to climb bushes and trees (2) (3) (4) (5).
Franklin’s ground squirrel has a varied diet which comprises a range of plant and animal material, including seeds, roots, shoots, leaves, buds, flowers, bulbs, vegetables and fruits, as well as insects, amphibians, fish, young birds, bird eggs and small mammals (2) (3) (4) (5) (6) (7). It will even eat young rabbits and other ground squirrels, and has been known to kill adult ducks and poultry (2) (4) (5) (7). Animal matter usually makes up around a third of the overall diet of this species (5) (6) (7).
Only spending around ten percent of its time above ground (1) (5) (7), Franklin’s ground squirrel lives the rest of its life in an underground burrow which it typically digs into a bank, hill or other steep slope, in well-drained soil (1) (2) (6). The burrow may have two or three entrances (2) and many branches, one of which has a nesting area lined with dried plant material (2) (6). Other branches may be used to store food or as latrines (2) (5).
Franklin’s ground squirrel is one of the least social members of its genus (2), usually living in small, loose colonies which rarely number over 10 to 12 individuals (4) (5). Its populations appear to fluctuate, peaking around every four to six years (1) (2) (5) (6), and this species will often stay in an area for a short period of time before disappearing and setting up a colony elsewhere (4) (5).
During the summer months, Franklin’s ground squirrel accumulates a thick layer of body fat to see it through the long winter hibernation period (2) (5). Individuals usually enter hibernation around late September (1) (4) (6), although in some northern areas they may become inactive as early as July (8). Males are the first to enter hibernation, while juveniles are the last, as they need extra time to build up sufficient fat reserves (2) (4) (5) (6). Several Franklin’s ground squirrels may hibernate together in the same burrow (2) (5).
The hibernation period of Franklin’s ground squirrel lasts around seven to eight months, with males not emerging again until late March or April. The female Franklin’s ground squirrels emerge from hibernation around one to two weeks after the males (2) (4) (5) (6) (9), but juveniles may not appear until as late as June or July (9). Breeding begins immediately after emergence, with male Franklin’s ground squirrels establishing dominance hierarchies (2), and mating occurring as soon as the females appear (2) (4) (5) (6).
The female Franklin’s ground squirrel gives birth to a single litter of between 5 and 11 young, usually in May or June, after a gestation period of 28 days (1) (2) (4) (5) (6). The young are born naked and blind (2) (5), and spend a month inside the burrow before emerging above ground (4) (5). Weaning takes place at about 40 days old (1) (4). After remaining with the female for several more weeks, the young Franklin’s ground squirrels disperse, and they develop rapidly, nearing full adult size by the autumn (4) (5) (7).
Both the male and female Franklin’s ground squirrel become sexually mature in the first spring following their birth (5) (6). Females may live for up to five years, but males usually only live for one to two years (2). Franklin’s ground squirrel may fall prey to a number of predators, including foxes, coyotes (Canis latrans), American badgers (Taxidea taxus), hawks, weasels, skunks and snakes (2) (4) (5) (6) (7), but failure to store enough body fat for hibernation may also be an important cause of mortality in juveniles (6).