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Finding Franklin’s

Story By Jenny Duggan, Ed Heske, Bob Schooley and Aimee Hurt Photos By Jenny Duggan

2 / Outdoor Illinois June 2009 30 days later. The young grow rapidly Man’s best friend may be just what and are ready to disperse by August or early September. Juvenile females usual - is needed to track down Illinoi s’ most ly settle close to home, but young males roam more widely in search of a secretive ground . new place to live, hopefully near unre - lated females. n Illinois, blooming daf - on the other hand, look similar to tree fodils and singing robins —large and speckled grey, but are heralded as signs of with a smaller tail. Like most ground squirrels, spring. However, for some Franklin’s spend about three-quarters of mammalian ecologists, the year underground hibernating. the emergence of ground Males emerge first each spring, around squirrels from the deep mid-April, and females emerge about in which they’ve two weeks later. Females remain close bIeen hibernating marks the to their burrows, but males typically true beginning of the season. search a larger area for prospective mates. A single litter of about seven to Two of ground squirrels can nine young is born in early June, and be found scampering above ground in juveniles appear on the surface about Illinois come spring: The thirteen-lined ( tride - Aimee Hurt, with Working Dogs for cemlineatus ) and Franklin’s ground Conservation, is training high-energy squirrel ( Spermophilus franklinii ). shelters dogs, such as Wicket, to Thirteen-lined ground squirrels are small, striped and a bit larger than a determine if they will be able to locate . Franklin’s ground squirrels, Franklin’s ground squirrels by smell. June 2009 Outdoor Illinois / 3 Typical Franklin’s ground squirrel habitat consists of slightly sloped, well-drained land with tall grasses and some trees and brush.

Franklin’s ground squirrel populations to survive? If so, the cause of the squir - rels’ decline might not simply be a decrease in the amount of suitable habi - tat, but also involve the increased dis - tances (or hardships) squirrels must travel through to find remaining areas of suitable habitat. Dispersal among habitat patches is important to help maintain the small colonies occupying each patch through immigration, re-col - onization of patches after local extirpa - tions and promoting genetic diversity by preventing inbreeding. To get to the root of the problem, INHS is surveying Franklin’s ground squirrels in Illinois and adjacent states Adult males already may be under - While thirteen-lined ground squirrels to determine where the squirrels are ground for the remainder of the year by prosper in human-managed landscapes, present. This information will be used late July, with adult females going under - Franklin’s ground squirrels are listed as to determine exactly what kind of habi - ground around late August. Juveniles threatened in the state of Illinois. tat the squirrels need and estimate how need time to pack on more body mass to Franklin’s also are less social than any much of this habitat remains in Illinois. survive the winter, and to disperse if they other species of ground squirrel and The second aspect of the study will are going to, so they typically go under - occur in small groups of widely dis - be to determine how the squirrels move ground in early September. Obviously, persed individuals rather than noisy, through the agricultural landscape that for these has more crowded colonies like western species. covers most of our state. By tracking the to do with minimizing predation risk and The Illinois Natural History Survey is movements of radio-collared squirrels as conserving energy than just avoiding the studying the causes of the decline of they make decisions while traveling cold. Mortality is highest during the first Franklin’s ground squirrels, as well as (e.g., “Should I take a shortcut though year of life, but if a Franklin’s ground what can be done to prevent the squir - the cornfield or go all the way around? squirrel makes it through that first win - rels from disappearing completely. Should I cross this busy, open road or ter, it might live 4-5 years. There isn’t a lot of tall grass habitat left turn around and go back?”), an under - Sightings of thirteen-lined ground in the Midwest, but the burning ques - standing of what acts as a barrier to squirrels are common in the short grass - tion is: Is there still enough for movement between areas of suitable es of lawns, parks and cemeteries. ) . Because Franklin’s ground squirrels are r e t s i g

secretive and prefer living in tall, dense e R - l a n

grasses where they are not easily spotted r u o J e

by humans or predators, most Illinoisans t a t S d

will never see this squirrel. However, l e i f g n Franklin’s ground squirrels also are a rari - i r p S ,

ty because the tall grasses that used to g n u o

be found in prairie and savannah habi - Y s i r h

tats have all but disappeared in Illinois. C y s e t r u o c o

Smaller than a gray squirrel, the t o h P Franklin’s ground squirrel’s tail is ( about as long as its body.

4 / Outdoor Illinois June 2009 ) . squirrels. The Montana-based non-profit S H N I

unding for this project has been , s

organization adopts high-energy, toy- a e received from the U.S. Fish and r y

F p Wildlife Service, University of Illinois at obsessed dogs from local shelters and S g e r

Urbana-Champaign, Illinois State Acad - trains them to identify a study or G y s e

emy of Sciences and American Society t its scat by smell, and to signal to their r u o

of Mammalogists. c o

handlers every time they pinpoint that t o h P smell. Instead of researchers spending ( habitat, and whether these barriers are days searching fields, roadsides and rail - getting to be too much for the squirrels road rights-of-way for burrows, then to handle, can be determined. setting live traps over three to four days Of course, surveys for Franklin’s to determine whether Franklin’s ground squirrels can be frustrating ground squirrels are present in an area, given how difficult it is to find these they may be able to conduct a survey secretive squirrels. That’s where man’s with a detection dog/handler team in a best friend steps in. matter of hours. INHS and University of Illinois researchers are collaborating with Working Dogs for Conservation to test or additional information on Work - whether trained detection dogs can be F ing Dogs for Conservation, visit www.workingdogsforconservation.org used to sniff out Franklin’s ground

Knowing your ground squirrels ) .

Franklin’s ground squirrel R J S d Spermophilus franklinii l e i f g n i Weight: males 370-500 g, females 340-425 g r p S

Description: ,

Gray head with whitish eye-ring, mottled g n u

gray to brown back, light gray undersides, bushy gray o Y s i tail about as long as the body length. Smaller than a r h C

gray , but almost two times larger than a y Reliance on prairie and savannah s e t r

thirteen-lined ground squirrel. u o Habitat: c habitats, both in decline in Illinois, has Tall grass, shrublands and woodland edges, o t o h

disturbed areas with tall grass or weeds as long as the P ( resulted in the Franklin’s ground soil is well drained, such as railroad rights-of-way. Will vacate mowed areas. squirrel being listed as a state-threat - Diet: Mostly green vegetation, seeds and insects. The most carnivorous of ground squir - ened species. rels, Franklin’s also are known to eat mice, toads, small and the eggs of ground- nesting birds, such as ducks, when they find them. Range: Occurs from northwestern Indiana through Nebraska, north through the Dako - Man’s best friend, indeed. tas into the aspen parkland and central prairies of Canada. In Illinois, Franklin’s occurs in Each spring, when you see the first the northern two-thirds of the state, south to about the Shelbyville moraine. flowers blooming and hear the birds Status in Illinois: Uncommon, listed as state-threatened in 2004. singing, remember that there are other ) . signs of spring, too, but some of them e Thirteen-lined ground squirrel d d o Spermophilus tridecemlineatus

H may be best found by sniffing. e l e

d Weight:

A 110-140 g, sexes similar y b Description: Thirteen alternating pale and dark o t o

h stripes on the back, with lines of pale spots in the dark P ( stripes. Tan to golden sides and underside, and along Jennifer M. Duggan is a Ph.D. candidate, edges of tail. Tail about two-thirds the length of the Department of Animal Biology, University body, and not as bushy as that of a Franklin’s or tree of Illinois at Urbana-Champaign. Dr. squirrel, more like that of a chipmunk. Edward J. Heske is a mammalian ecologist Habitat: Short grasses, including mowed roadsides, with the Illinois Natural History Survey. lawns, cemeteries, and other human-managed areas, Dr. Robert L. Schooley is an assistant pro - although it also can be found in old fields and prairies if the grasses are not too tall and there are open areas between the clumps of grasses. fessor, Department of Natural Resources Diet: Mostly seeds and other plant material, plus a variety of insects and grubs. Thirteen- and Environmental Sciences, University of liners also will consume birds’ eggs and small lizards or snakes occasionally. Illinois at Urbana-Champaign. Aimee Hurt Range: Within Illinois, the ranges of Franklin’s and thirteen-lined ground squirrels are is the operations director with Working similar. However, thirteen-liners range farther east through Michigan, farther west Dogs for Conservation. through eastern Montana, Wyoming, and Colorado, and farther south through Oklahoma and Texas to the Gulf Coast. Status in Illinois: Common. June 2009 Outdoor Illinois / 5