BIRDS OF THE CAMBRIDGE REGION. 



41 



their numbers steadily increased until by the close of the past century it was 

 not unusual for two or three hundred Ducks, and twice or thrice as many Gulls, 

 to be assembled there at one time. The presence of so many large and con- 

 spicuous birds in a city park attracted general attention, of course. Unfortu- 

 nately it also gave rise to fears that, as the pond was used as a reservoir, its 

 waters were in danger of pollution. Soon afterwards all the binls, but espe- 

 cially the Gulls — although, as every ornithologist knows, most cleanly birds 

 and of great value as scavengers — were voted a nuisance, and the park police- 

 men were ordered to frighten them away from the pond by the use of guns 

 loaded, as a rule (but not invariably, as I have reason to know), with blank 

 cartridges. This practice — begun eight or ten years ago — has not been kept 

 up very systematically, however, and whenever it is discontinued for any length 

 of time the birds become numerous again. 



Most of the Ducks which frequent the pond at the present day are ]5iack 

 Ducks, represented by both the red-legged and green-legged races. The former 

 occurs only in autumn, winter and early spring, but the green-legged bird breeds 

 in the neighboring swamps and often alights in the pond in midsunmier. Be- 

 sides the Black Ducks, there have been seen within recent years Canada Geese, 

 Mallards, Green-winged Teal, Pintails, Lesser Scaups, Whistlers, Ruddy Ducks 

 and two species of Mergansers. The Canvas-back has also been noted once, and 

 the Redhead on several occasions. Coots {Fii/ka) occur rather commonly, and 

 Pied-billed Grebes not infrequently, while Loons have been occasionally seen of 

 late. Nearly all of these birds appear only in autumn, when many of them spend 

 weeks at a time in the pond. The diving species remain there night and day 

 during their stay, but the surface-feeding kinds such as the Black Duck, Mallard 

 and Teal, obtain most of their food along the seacoast, to which they resort at 

 night, returning to the pond in the early morning. 



Nearly all the Gulls are Herring Gulls, but among them one may often see 

 a few Black-backs, and rarely an Iceland or a Glaucous Gull. Like the surface- 

 feeding Ducks, the Gulls obtain most of their food in salt water, although during 

 their visits to the pond they pick up and devour many a dead or dying fish 

 which would otherwise be left to pollute the water. These visits are made 

 chiefly during the forenoon, and the birds appear most numerously when the 

 weather is calm and mild. 



