Let's quickly dispel one rumor about the most conspicuous animal on campus, the gray squirrel. After an extensive search of the scientific literature, I conclude that gray squirrels could not possibly be reincarnated Penn State alumni. However, after searching the same extensive literature, I cannot refute a second rumor that gray squirrels on the Old Main lawn are reincarnated Penn State presidents.
Gray squirrels often are seen on campus hoarding nuts and other items to survive winter. Because gray squirrels are not territorial, other squirrels can raid the nuts stored by another squirrel. Despite the possibility of theft, hoarding of food by gray squirrels is presumably adaptive because individual caches are abundant, widely scattered and inconspicuous. A squirrel finds a stored food item using both olfactory cues and visual cues, such as disturbed soil or the location of landmarks (large logs, for example), and memory of the location of the stored food item.
Gray squirrels are native to our region, having evolved in the eastern forests of North America. But the gray squirrel has been introduced into western North America, from California northward into British Columbia, and to other parts of the world, such as Great Britain, South Africa and Australia, and, hence, is an exotic species in some locations.
The native gray squirrel does not compete with other squirrel species, such as the fox squirrel, in the eastern deciduous forest. Gray squirrels in both the eastern and western United States, however, can occasionally become a nuisance to humans by entering attics, gnawing on wires or feeding on seed intended for backyard songbirds.
But a different story can be told about the gray squirrel in Great Britain, where its introduction has unfortunately "backfired" with possible serious consequences to a native squirrel, the Eurasian red squirrel.
Only two species of squirrels are found in Britain today -- Eurasian red squirrels and gray squirrels.
Gray squirrels were introduced into country parks and estates of southeast England from the United States in 1876. Thereafter, populations quickly spread in England, and by 1930, were considered pests in deciduous forests.
The range of the Eurasian red squirrel then contracted sharply through the 1940s and 1950s, being restricted to some offshore islands and large coniferous tracts of forest in northern England and Scotland.
Two principal reasons have been proposed for the decline of the Eurasian red squirrel in Great Britain in the 20th century: disease outbreak and interspecific competition. Yet the increase in American gray squirrels coupled with a decline in Eurasian red squirrels in Great Britain may be best attributed to changing landscapes over the past few decades, with large tracts of deciduous woodlands replacing coniferous woodlands. Deciduous woodlands are preferred by gray squirrels, whereas coniferous woodlands are choice habitat for red squirrels. Therefore, the long-term conservation of Eurasian red squirrels may hinge on the retention of large coniferous forest stands devoid of deciduous trees as home sites for red squirrels, although wildlife authorities in Great Britain believe the red squirrel is currently not in danger of extinction in the near future. But the preservation of coniferous stands poses a dilemma for conservationists in Great Britain because coniferous forests typically support a much lower diversity of wildlife than deciduous stands.
Hence, a value judgment needs to be made by British wildlife biologists between the benefits of ensuring coniferous habitat for the declining Eurasian red squirrel versus providing a greater diversity of species in deciduous forests.
In conclusion, as we sit quietly watching a gray squirrel feeding in a local park or in our backyard, we may remind ourselves that even this species, when placed in an exotic land, can "backfire" and become a real pest.
So, if gray squirrels become a problem on Old Main lawn by playing too much frisbee, how can it be handled by administration? Hide the frisbees, it drives squirrels nuts. Or, how can students be helpful in capturing gray squirrels if squirrels suddenly overpopulate campus? Students can climb trees and act like nuts.
