344 Life-histories of Northern Animals 



ten times as many might have been seen. Already (September 

 i6), apparently, some of them had retired for the season. 



Along the wooded banks of the Red River and Assiniboine 

 River, the tangled brushy banks afford to the Chipmunks good 

 concealment as well as plenty of nut and seed supplies. Here, 

 though they are less abundant than at Ingolf, I found them so 

 generally distributed that it would be safe to estimate their 

 number at a pair for every fifty yards along the river front. 



At Cos Cob, Conn., the species abounds. Along the drive 

 which passes through the woods for 700 yards, I found 7 or 

 perhaps 8 pairs. This would give about i pair to each acre. 

 A favourite hollow just back of the house, however, has as 

 many as the entire drive, although it is less than half an acre 

 in extent. 



One pair to the acre is over 1,000 Chipmunks to the square 

 mile, and this I should say is well within their numbers in all 

 the half-cultivated parts of their range in years of abundance. 

 But in places of high cultivation like Ohio, and south-western 

 Manitoba, or of no cultivation at all, like northern Ontario and 

 north-eastern Manitoba, I should divide the figures by 100, and 

 on this basis reckon up the Chipmunk population of their 

 entire range at not less than 20,000,000 in years of abundance, 

 and in years of disaster, reduce it to a quarter as many. 



sociA- The Chipmunk is quite sociable as well as gregarious. 



BILITY . . . 



Not only do they associate in numbers where the surroundings 

 are attractive, but they unite in several efforts, notably the 

 spring chorus described later, and, as Kennicott remarks,* 

 "sometimes, though not always, several pairs occupy the same 

 burrow in winter, the store of food being common property." 



Some interesting observations on their sociability are thus 

 supplied by John Burroughs.^ 



"One March morning after a light fall of snow I saw 

 where one had come up out of his hole, which was in the side 

 of our path to the vineyard, and after a moment's survey of the 

 surroundings had started off on his travels. I followed the 



* Quad. 111., 1857, p. 72. ^ Squir. and Furbearers, 1900, pp. 23-24. 



