"a number of squirrels swiming the Ohio"
Eastern gray squirrel, Scuirus carolinensis Gmelin
Lewis wrote a description of the eastern gray squirrel, the first of his natural history observations, on September 11, 1803, twelve days after he left Pittsburgh on his voyage down the Ohio.
Lewis noticed the migration every day for the rest of the week, but wrote no more about it. He continued to pay attention to the species, however, finally recording the observation that he had seen it as high up the Missouri as the mouth of the Little Sioux River, 733 miles from the Mississippi by Clark's estimate.1 It came to mind on June 10, 1806, as the Corps was at Weippe Prairie preparing to recross the Bitterroot Mountains. "We find a great number of burrowing squirels about our camp," he wrote—referring to the Columbian ground squirrel, Spermophilus columbianus—"of which we killed Several; I eate of them and found them quit as tender and well flavd. as our grey squirel."
He was right about the attraction of mast—the accumulation of nuts on the ground. The migration might have been a sign of the species' response to competition for mast from the more numerous passenger pigeons,2 which were particularly fond of acorns and beech nuts. But he was wrong about the climate issue. Those black squirrels merely represented a melanistic color phase of the species that is common in the northern regions of its range. Generally, its color ranges from grizzled dark to pale gray, often with cinnamon-toned patches.
The furry-coated, bushy-tailed, bright-eyed little rodent had already been described and officially given the scientific name, Sciurus carolinensis—"squirrel of carolina,"—by the German naturalist Johann Friedrich Gmelin (1748-1804) in 1788. The generic name Scuirus is from the Greek skuiros, meaning "shade tail," in reference to one of the practical functions of the animal's characteristically bushy appendage, which also serves as an umbrella, a blanket, and a rudder when swimming. Obviously, the common name is an Anglicized version of the Greek name.
In 18th-century America these ubiquitous rodents, with pestilential persistence, triumphed over humans' laws and money. "This species," wrote the Philadelphia naturalist John Godman,
was once so excessively multiplied as to be a scourge to the inhabitants, not only consuming their grain, but exhausting the public treasury by the amount of premiums given for their destruction. "Pennsylvania (says Pennant3) paid from January, 1749 to January, 1750, eight thousand pounds of currency; but on complaint being made by the deputies that their treasuries were exhausted by these rewards, they were reduced to one half." How improved must the state of the Americans then be, in thirty-five years to wage an expensive and successful war against its parent country, which before could not bear the charges of clearing the provinces from the ravages of these insignificant animals!4
Godman himself reserved a measure of admiration for the little mammal.
This species is remarkable among all our squirrels for its beauty and activity. It is in captivity remarkably playful and mischievous, and is more frequently kept as a pet than any other. It becomes very tame, and may be allowed to spend a great deal of the time entirely at liberty, where there is nothing exposed that can be injured by its teeth, which it is sure to try upon every article of furniture, &c. in its vicinity.
Nowadays they sometimes exercise their jaws on power lines, which occasionally fries the squirrel and interrupts the service. It is now illegal to keep a squirrel as a pet, but hunting is permitted in most states. The season for "bushytails" in Ohio, for example, currently (2006) extends from September first to the end of January. Recipes for preparing squirrel meat for the table are too numerous to count.
Eastern gray squirrels are remarkably swift and agile, which usually enables them to elude the hawks and eagles that are their principal predators. Also, as Meriwether Lewis observed, they are excellent swimmers. The life span of eastern gray squirrels extends to a maximum of twelve years. Each female bears two litters of two or three offspring each year, in nests built high in the trees. Their fecundity as well as their adaptability to any wooded environment, and especially urban parks, has so far guaranteed their survival as a species. With the influx of settlers into the Ohio and Mississippi River valleys during the 19th century, however, the gray squirrel population declined commensurately, partly as a consequence of the little critter's appeal at the dinner-table, but mostly owing to the destruction and fragmentation of the woodland habitat it favored. In the state of Illinois, for example, nearly three-quarters of the original woodlands have been cut down since 1820.5
1. "Postexpeditionary Miscellany," Moulton, Journals, 8:416.
2. This avian species, once the most numerous in the world, was extirpated from North America by the end of the 19th century. The last specimen in captivity died in 1914 at age 29, in the Cincinnati Zoological Garden.
3. Thomas Pennant (1726—1798) was a Welsh naturalist and world traveler whose History of Quadrapeds (1781) and Arctic Zoology (2 vols., 1784-85)—chiefly of North America—established him as one of the foremost zoologists of his generation. Godman's quotation is from Arctic Zoology, 2:135.
4. John D. Godman, American Natural History, 3 vols. (Philadelphia: Carey, Lea & Carey, 1828), 2:131.
5. "What Color Are Your Squirrels," Illinois Natural History Survey, Reports (May-June 1997). http://wwx.inhs.illinois.edu/resources/inhsreports/may-jun97/color/ (accessed December 3, 2015).
Funded in part by a grant from the Idaho Governor's Lewis and Clark Trail Committee.