54 
JOURNAL OF MAMMALOGY 
The farmers in the Western wilds regard them with sensations which may be 
compared to the anxious apprehensions of the Eastern nations at the flight of the 
devouring locust. At such periods, which usually occur in autumn, the squirrels 
congregate in different districts of the far Northwest; and in irregular troops 
bend their way instinctively in an eastern direction. Mountains, cleared fields, 
the narrow bays of our lakes, or our broad rivers, present no unconquerable 
impediments. Onward they come, devouring on their way everything that is 
suited to their taste, laying waste the corn and wheat-fields of the farmer; and 
as their numbers are thinned by the gun, the dog, and the club, others fall in 
and fill up the ranks, till they occasion infinite mischief, and call forth more than 
empty threats of vengeance. (B.) 
Ordinarily averse to entering the water, they now take to it boldly, and though 
swimming with difficulty, manage to cross broad rivers, like the Niagara and the 
Ohio, though many are drowned in the attempt 
Sometimes, when on these migrations, especially after crossing rivers, the 
squirrels become so fatigued as to be easily captured, and thousands are then 
killed by boys armed merely with sticks and stones. I learn from Dr. John A. 
Kennicott that, during one of these migrations, innumerable squirrels swam 
across the river Niagara, and landed near Buffalo, New York, in such a state of 
exhaustion that the boys caught them in their hands, or knocked them from the 
fences and bushes with poles. (K.) 
They swam the Hudson in various places between Waterford and Saratoga; 
those which we observed crossing the river were swimming deep and awkwardly, 
their bodies and tails wholly submerged; several that had been drowned were 
carried downwards by the stream, and those which were so fortunate as to reach 
the opposite bank were so wet and fatigued, that the boys stationed there with 
clubs found no difficulty in securing them alive or in killing them. Their migra- 
tions on that occasion did not, as far as we could learn, extend farther eastward 
than the mountains of Vermont; many remained in the county of Rensselaer, and 
it was remarked that for several years afterwards squirrels were far more numer- 
ous there than before. It is doubtful whether any ever return to the west, as, 
finding forests and food suited to their taste and habits, they take up their per- 
manent residence in their newly explored country, where they remain and pro- 
pagate their species, until they are gradually thinned off by the increase of in- 
habitants, new clearings, and the dexterity of the sportsmen around them. (B.) 
AFTER THE TREK 
After one of these grand migrations, very few of the species are found in the 
localities from which they have moved, and these, as if alarmed at the unusual 
solitude, are silent and shy. They rapidly increase in numbers, however, and, 
in a few years, are as abundant as before. I am not aware that they ever migrate 
except when exceedingly abundant. Of these immense hordes, but few probably 
survive. No sudden increase in their numbers was heard of in Southern Wis- 
consin after the several migrations from Northern Illinois. Many are drowned 
in attempting to cross streams as has been stated; not a few are destroyed by 
man; some die from utter exhaustion; and, when thus forced to travel, in an 
unnatural manner, upon the ground, they fall an easy prey to rapacious birds 
and mammals, all of which feast when the squirrels migrate. (K.) 
