White squirrels settling in
White squirrel fans now have more to love (and post to social media). It's fairly certain that central campus is home to more than one, said Tim Stewart, associate professor in natural resource ecology and management.
Stewart surmises that the genetic mutation that causes "leucism" (loss of pigment in squirrels, birds and other animals) is in the campus squirrel population and will continue to be expressed in white or light variations of the normally orange-brown squirrels of ISU.
Where to see white squirrels
- Central campus, between Curtiss and Catt halls
- Near Lake LaVerne
- Between Hamilton Hall and Food Sciences Building
Sightings of a white squirrel on campus began around 2000. Stewart said it's not likely that squirrel is still around (in the wilds, squirrels often don't live beyond three years), but we may be seeing descendants. The gene responsible for leucism likely is recessive but it may persist in the squirrel population, just like blue eyes and other recessive traits endure among humans, he said.
Leucistic, not albino
Leucistic squirrels and other animals are often confused with albinos. It's easy to make the call by looking at the animal's eyes, Stewart said. If the animal has the same eye color as others of its species (Iowa State's dark-eyed white squirrels do), they're leucistic. Technically, leucism involves partial loss of pigmentation, which gives animals varying degrees of whiteness. One of Iowa State's squirrels has light fur with patches of brown showing through on its face and tail. Albino animals, on the other hand, completely lack melanin, the pigment that lends color to fur and skin; albino animals are white all over with pale often-pinkish eyes.
Campuses make nice habitats
White squirrels stand out in forests and are more likely to be picked off by predators, Stewart said. Campuses seem to provide a relatively safe haven for both white and brown squirrels, and a number of universities around the country report having white squirrel populations.
They're fox squirrels … and tree planters
Iowa State's white squirrels, like most of the squirrels on the ISU campus, are fox squirrels, Stewart said. Their Iowa City campus cousins are gray squirrels. Those big, ball-shaped nests of sticks and leaves high up in the trees are fox squirrel homes. These squirrels also make their nests in large tree cavities.
Squirrels really do squirrel away nuts, for later recovery in the winter, Stewart said. However, they also leave behind a number of buried seeds, thus helping in reforestation. A lot of the trees in Pammel Woods, south of Veenker Golf Course, were probably sown by squirrels, he added.