Endangered Squirrels' Numbers Down
TUCSON, Ariz. A wildfire that charred 29,400 acres on Mount Graham last year may have contributed to a decline in the population of endangered red squirrels, whose numbers are now at their lowest levels since 1991.
The decline isn't a cause for panic, U.S. Fish and Wildlife Service biologist Thetis Gamberg said, but added, "Everyone's radar goes up when it looks like your numbers are going down.
The red squirrel population has been estimated at 214, according to a spring survey based on visits to the middens where squirrels store food. That's 50 fewer squirrels than last fall's estimate and less than half the peak in the late 1990s, when an insect outbreak began to ravage the ancient spruce-fir forest atop Mount Graham.
Scientists are certain some squirrels died during the fire, which also threatened a multimillion-dollar observatory and about 100 summer homes and cabins last July before rains knocked it down.
But their concern has centered on how the blaze affected the habitat used by the red squirrels, which have been stranded atop southern Arizona's tallest mountain range since the end of the last Ice Age.
Tim Snow, an Arizona Game and Fish Department biologist who coordinated the survey, said that between 13 percent and 24 percent of the squirrels' middens were lost because of the fire.
He said the recent population decline falls within that range but drought and insect activity also may be having an effect.
"If we continue to have a wet year this year and next, we could see another spike in the population," Snow said. "Certainly we're hopeful it won't go down much lower than this."
The squirrels have been on the endangered list since 1987 and were at the center of environmentalists' failed efforts to block the University of Arizona from building three telescopes on Mount Graham, 75 miles northeast of Tucson.
Source: Associated Press