ENGLISH SPARROW 5 



from 2,705, an average of 13.7 per day, between November 20, 1914, 

 and January 1, 1916, to only 570, an average of 5.6 per day, between 

 January 1, 1921, and June 28, 1922. He claims to have kept a careful 

 record and "accurate account of every bird seen at any time." 



According to W. H. Bergtold (1921), there was a marked decrease 

 in the number of English sparrows in Denver, Colo., during the 15 years 

 previous to 1921. His observations were made in "a well grassed and 

 timbered area surrounding the Court House," opposite his office; he 

 estimated conservatively that 15 years ago "the sparrow population 

 of this area * * * could not have been less than one thousand birds." 

 Careful counts made by him on 7 days in October 1919, in the same 

 area, varied from 5 to less than 20 birds seen each day. 



Considerable falling off in numbers has been noted in the cities and 

 towns of eastern Canada, but in the rural districts and in some of the 

 towns in the Prairie regions the decline in numbers is less marked and 

 the population has become more static. 



Natural causes do not seem to have been sufficient to account for 

 the decrease in numbers; English sparrows have no more serious 

 natural enemies than other birds; there is no evidence of any wide- 

 spread epidemics or diseases ; the elements have caused some wholesale 

 destruction in a few places, but other birds have recovered from the 

 results of such disasters. There remains a generally accepted cause, 

 the diminution in the food supply, especially in the cities. It is signifi- 

 cant that the decrease in the sparrow population in urban and suburban 

 areas coincides very closely with the increased use of motor vehicles 

 and the decrease in the number of horses that formerly spread a 

 bountiful food supply along our streets and highways. Even in the 

 farming districts, the tractor and other mechanical agricultural ma- 

 chines have largely replaced the horse; and in the cities and towns a 

 horse-drawn vehicle is a rare sight today. Bergtold (1921) gives us 

 some figures to illustrate the passing of the horse; official statistics 

 show that, in Denver, the number of horses declined from 5,904 in 

 1907 to 3,832 in 1917, a reduction of about 33 percent. He says 

 further: "There can be, however, little^question concerning the reality 

 of the 'vanishing horse', for it has been shown (Saturday Evening Post, 

 Sept. 13, 1919) that the number of horses in New York City recently 

 declined from 108,036 to 75,740, and it is probable that what amounts 

 to decrease (by displacement or substitution) has occurred also in 

 suburban areas, since statistics seem to show a decrease or displace- 

 ment of 33% of the horses in one of the Dakotas. Finally in this 

 connection it can be said that early in November 1919 there were 

 enough tractors in use in Colorado to displace 16,000 horses." 



The above is largely ancient history, but the figures show the trend, 

 which has been going on ever since at an increasing rate until the 



