-- Squirrel populations as close as two miles apart are no longer mixing.
-- The farther apart populations are geographically, the more different they are genetically, suggesting that they have been separated longer, and that little or no dispersal is occurring between populations today.
The biologists' hypothesis -- that inadequate nutrition is one cause for the squirrels' disappearance -- received a boost from an "accidental experiment," when cattleman Frank Anderson moved to a remote house on the OX Ranch. Within a year, the Idaho ground squirrels around Anderson's residence were reproducing like rabbits and doubling their weight during the summer months, just like hibernating animals are supposed to.
Sherman and Gavin quickly pinpointed the cause of the population explosion: Seed-starved squirrels were eating kibble the rancher left outdoors for his herding dogs, as well as spilled oats from horse feed.
Now the dog chow-fed squirrels are part of a deliberate experiment by the Idaho Department of Fish and Game, the U.S. Forest Service and researchers from Cornell and Albertson College:
-- Controlled, "cool" fires are set to burn off non-native vegetation and underbrush that blocks the ground squirrels' movement from one population patch to others. Unlike hot, uncontrolled wildfires, the controlled burns should not destroy seeds of native plants, including some that require heat to germinate.
-- Burned meadows are reseeded to reintroduce native plants that the ground squirrels and other wildlife need.
-- Healthy squirrels from the ranch house population are humanely trapped and moved to prepared sites in burned and reseeded meadows. The biologists even dig burrows with power augers, giving the squirrels a head start in establishing new homes.
"It's not Purina dog chow, but they're finally getting plenty of the
leaves and fat-rich seeds of native grasses
'"/>
Contact: Roger Segelken
hrs2@cornell.edu
607-255-9736
Cornell University News Service
3-May-1999