November 2007 OutdoorIllinois / 9

Not long ago,both red and

gray foxes werecommon in

Illinois.Today,Illinois is a

red state.

TheGrayFox

PuzzleStory By Joe McFarlandPhotos By SIU CooperativeWildlife Research Laboratory

Illinois has long been home totwo different species of fox—the red and the gray—scientifi-cally called Vulpes vulpes andUrocyon cinereoargenteusrespectively. And, for as long asanyone can recall, populations

of both species were roughly the samesize. In various regions of the PrairieState, individual red or gray fox popula-

tions might fluctuate from one year (ordecade) to the next—more reds ormore grays. But, overall, balanced pop-ulations were typical.A few numbers, for example: In the

winter of 1977-78, Illinois hunters andtrappers harvested 9,715 red foxesstatewide. In the same season, furtakersharvested 9,086 gray foxes. The differ-ence was statistically inconsequential.But, about 25 years ago, something

began to change. By 1983, harvest fig-ures for red fox remained relativelyunchanged at 9,780—but only 5,943 forgray foxes. And with each passing year,the decline of gray foxes continued.

Including today. Last winter, a mere67 gray foxes were harvested by Illinoistrappers, compared against 989 redfoxes. While there are far fewerlicensed trappers in Illinois than thereused to be—and fur prices often have adirect influence on harvest totals—itbecame increasingly apparent, as years

Populations of gray foxes in Illinois

have declined significantly during the

past 25 years. In contrast, coyote

populations statewide have increased.

10 / OutdoorIllinois November 2007

passed, that fewer gray foxes were trot-ting around the fields and forests of thePrairie State.For wildlife biologists, the reasons

weren’t immediately clear, based onwhat was known about fox ecology inIllinois. Harvest results weren’t the onlyindicator used to monitor fox popula-tions in Illinois; sightings reported byarchery deer hunters in annual surveysby DNR also shed light on the overallstatus of fox populations. Yet more datawere needed.In response to the decline in gray

fox populations, two research teams—one in northern Illinois, and one insouthern Illinois—began collectingfield data in 2005 in an effort to betterunderstand the status of the gray fox inIllinois. Researchers at Max McGrawWildlife Foundation and at SouthernIllinois University’s CooperativeWildlife Research Laboratory devel-oped strategies to live-trap, radio col-lar, then track and monitor as manygray foxes as they could to uncover thepossible sources of a decline.Aside from the obvious color

variations, most people don’t realizethe differences between red and grayfoxes.“Gray foxes seem to prefer early suc-

cession forest habitat,” explained BobBluett, furbearer program manager forthe Department of Natural Resources.

“In comparison, red foxes are typicallymore of an open grassland species.You’re more likely to find a gray fox inthe woods, and red foxes in fields,hunting along fence rows—or almostanywhere else.”Those differing preferences: Could

it be possible the necessary woodlandhabitat for gray foxes was shrinking?Or were other factors, such as diseaseor predation, involved? Bluett saidhabitat loss alone doesn’t appear to bethe sole culprit.“Gray foxes are found in small num-

bers throughout Illinois,” he said. “Butsince the habitat across the state is sovaried, with gray foxes living in all of

those habitats, we have to look in morethan one place to find answers.”Diseases such as canine distemper

(which can affect red foxes as well asgray) weren’t significantly affectingfoxes, so attention was focused onpredators. In particular, one Illinoismammal which has increased andexpanded its range in Illinois during thepast 25 years deserved a closer look.“The 70s is when the coyote popu-

lations in Illinois really took off,”Bluett noted. To what extent predato-ry coyotes were connected to thedecline of gray foxes soon became astudy target, and the correlationseemed to make sense.

Researchers from the Cooperative

Wildlife Research Laboratory at Southern

Illinois University fit a radio-telemetry

collar to a live gray fox.

Although the fur of the gray fox (above)

includes a considerable amount of red

color, the overall gray color distinguishes

the species. The tree-climbing ability

(right) separates foxes from coyotes.

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Coyotes and foxes don’t get along,and the larger coyotes often win out.Since red foxes have shown the abilityto hide in suburban and even urbanareas (places gray foxes appeared reluc-tant to visit), was it possible that coy-otes were killing off gray foxes in theirwild habitat?Ohio State University wildlife biolo-

gist Stan Gehrt—one of the researchersinvolved in the study—said the investi-gation uncovered a twist.As part of the field team for the Max

McGraw efforts in northeastern Illinois,Gehrt documented coyotes trackingdown and killing gray foxes in unbeliev-able locations.“We identified a family of gray foxes

living in a cemetery in an intenselyurban area on the south side of Chica-go,” Gehrt said. “The amazing thing is,it was a place nobody would expect tofind even a red fox. On top of that, coy-otes still found their hiding spot andkilled them.”Coyotes now live in all areas of Illi-

nois, including the most urban areas ofdowntown Chicago. Yet, despite thecoyote presence, there appears to be ameasure of safety for foxes in the cityand suburban areas (one family of foxesin the study took up residence under thedeck of a suburban home—an unlikely

home for coyotes—and the homeownerswelcomed the visitors). Gehrt suggestedthe early adaptation of red foxes to liveamong humans—long before gray foxesmade the switch—might have saved theoverall red fox population, but crushedthe population of “wild” gray foxes.In terms of predator/prey adapta-

tion, the increase in coyotes seemed tohappen so fast, the wild population ofgray foxes might have declined too farbefore some of them attempted to takerefuge in the city.Bluett said there is yet another

factor out there in the country to con-sider. The rural areas of Illinois wheregray foxes once lived have lost aprimary predator of coyotes. A shift inagricultural lifestyles toward larger,unoccupied farms with fewer individualfarmers removed one of the traditionalcoyote population controls in Illinois.

“There were a lot more people onthe rural landscape 30 or 40 years ago,and more people hunted,” Bluett said.“Farmers tended to do what wasnecessary to protect their interests,and coyotes would have been one oftheir targets.”With fewer coyote hunters, coyotes

could expand their base. Plus, anincreasing supply of food was suddenlyeverywhere.“Years ago, we didn’t have the deer

population we have now,” Bluettadded. “Coyotes clearly have plenty toeat in Illinois today.”As researchers collect additional

clues from the nearly 100 gray foxesthey’ve observed statewide, the publicis encouraged to join the effort. Anyonewho’s spotted a gray fox—includingroad-killed examples—is encouraged toreport the sighting to either the MaxMcGraw Wildlife Foundation in north-ern Illinois at (847) 428-6331, or theSIU Cooperative Wildlife Research Labin southern Illinois at (618) 536-7766.For the foreseeable future, Gehrt

said, both red and gray foxes—especial-ly the gray—will have to somehowendure large coyote populations.“They’ll either have to figure out

how to adjust to coyotes, or they’regoing to stay at very low levels for anumber of years.”

November 2007 OutdoorIllinois / 11

The previously undocumented details

of gray fox behavior, including habitat

use and preference, is detected through

radio telemetry.

Keeping handling stress to a minimum,

SIU researchers masked their study subjects

while preparing them for release.