DANCE 



382 Life-histories of Northern Animals 



a few minutes, and the growing crop at the door afifords bounti- 

 ful forage; thus it fits in very comfortably with agricultural 

 surroundings, and has greatly increased with the spread of 

 farming. 



In the Souris country, where there is abundance of wheat on 

 rolling clay lands, it finds an ideal home, and is very plentiful. 



ABUN-^ This is by far the most abundant of the Ground-squirrels. 



At Whitewater on April 29, 1904, I examined an interesting 

 colony of the species. In its centre of population I marked off 

 a space 10 yards by 20, then counted the burrows in it. 

 There were 50. This, I should think, meant at least 25 adult 

 Ground-squirrels in the space of less than one twenty-fourth of 

 an acre. The colony straggled along for a mile or more, the 

 population thinning out on the level fields to four or five holes 

 per acre, and of course with none at all in the wet places. But 

 taking all together, I calculated the Ground-squirrel population 

 at not less than 10 per acre, or, say 5,000 to the square mile. 

 That 10 per acre is not too high is shown in a case observed 

 on the Saskatchewan by James M. Macoun. A farmer there 

 killed 300 of these Ground-squirrels on his field of less than 10 

 acres, and yet it made no obvious difference in their numbers. 



E. T. Judd tells ^ of a square mile in North Dakota on 

 which 4,000 Ground-squirrels were killed in one season. 



In a two-acre field of wheat at Carberry, July 5, 1892, I 

 counted 16 Ground-squirrels sitting up. I could not see those 

 that were down on all-fours feeding, but it is safe to put them 

 at double this number. There were at least 50 Ground- 

 squirrels in that field, or 25 to the acre, and along the bank of 

 Pollworth's slough, north of Carberry, in the early 8o's I have 

 often seen as many as 50 Ground-squirrels within an acre and 

 there captured 20 in one hour with two traps. Even halving the 

 lowest of these figures, we should have a Ground-squirrel popu- 

 lation of 20,000,000 on the prairies of Manitoba alone. 



That these estimates are not excessive is shown by the 

 bounty records. At Carberry, in the year 1890, with bounties 



' Bailey's Rep. Prairie Ground-squirrels, U. S. Dep. Agr., 1893, Bull. No. 4, p. 65. 



