TUCSON — Richard Winstead spent weeks of tromping through grassy brush at 3 a.m., lugging a heavy backpack and shining a spotlight into the night looking for pairs of emerald-green eyes.
Finally, before dawn on Oct. 26, he and his colleagues at Arizona Game and Fish spotted their quarry--little masked critters staring back at them.
Three wild-born black-footed ferret kits they saw that night, and three more spotted the next night, offer hopeful signs that a reintroduction program is working.
"This was the first time we found a litter, so it's good news, because we finally are showing that they are capable of surviving long enough to have offspring," said Winstead, a state biologist. "You need that to have a successful population."
Since 1996, Winstead's Kingman-based team has been focused on nurturing a captive population of ferrets to return them to the wild.
The work is part of a broader U.S. Fish and Wildlife Service program to reestablish one of North America's most endangered animals in a stretch of the West encompassing Arizona, Wyoming, Montana, Utah, South Dakota, Colorado and northwestern Mexico.
Last May, Winstead and his team released 16 ferrets, including 10 pregnant females, in the Aubrey Valley, 30,000 square acres of grasslands and small shrubs between Peach Springs and Seligman in northwest Arizona.
The area has the state's highest density of Gunnison's prairie dogs, the ferret's favorite prey, and the release was timed to prairie dog birthings, Winstead said.
Ten of the released ferrets wore radio collars, but tracking them during the summer was unsuccessful.
Winstead's team also devoted 45 nights over five months last year to spotlight patrols, driving repeatedly on routes across the Aubrey Valley and trekking on foot through areas without roads.
Those on foot had to carry a motorcycle battery in a backpack to power the spotlight used to attract the ferrets' characteristic emerald-green "eyeshine."
Winstead described the search as "a needle-in-a-haystack sort of situation."
But he got lucky. The two male and four female kits were caught in humane traps and tagged with transponders, then released. The transponders--about the size of a grain of rice--emit an identifying signal when a ferret is placed within inches of a magnetic reader.
Three of the kits are believed to have been the offspring of a female released in May.
Other wild births have been recorded in South Dakota and Montana.
The nocturnal black-footed ferret--the only one native to North America--weighs about 1 1/2 pounds and is about 18 inches long. It's tan with a brownish-black raccoon-like facemask and has black feet and a black-tipped tail.
The ferret spends most of its life wriggling through prairie dog burrows. Its population shrank along with that of its prey, which falls victim to disease, poisoning and development.
Authorities estimate there are only 600 to 700 black-footed ferrets today, about half living in the wild.
Winstead said the reintroduction program will have two measures of success: survival in the wild for a year or longer, and reproduction.
For the Aubrey Valley, that would mean about 30 adults and their offspring, he said. The recent discovery of young is encouraging.
"What it means for that particular species is that we have better than a fighting chance of getting them reestablished here, despite unforeseeable things like disease outbreaks," said Bob Posey, Game and Fish regional supervisor in Kingman. "We know now that they can reproduce in the wild, and that's a major plus."