“a 
FOOD HABITS OF SHOAL-WATER DUCKS. Ds: 
and early in fall. It usually arrives in central Iowa during the last 
week in March, and at Aweme, Manitoba, about a month later. In 
the fall migration it reappears throughout the northern half of the 
United States during the month of August and reaches the Gulf of 
Mexico about the middle of September. In habits it is very similar 
to the green-winged teal, and like that bird its numbers have been 
ereatly diminished in recent years on account of its slight fear of man 
and the consequent ease with which it may be shot by even inex- 
perienced sportsmen. It is especially rare in most of the States east 
of the Alleghenies, and great care should be taken in some localities 
to see that it is not entirely wiped out. 
In general appearance the blue-winged teal is similar to the green- 
wing, having also a green speculum, which, however, is supplemented 
by a light-blue shoulder patch, separated from the green by a narrow 
white line. The adult male also lacks the white mark before the 
wing, which is present in the green-winged teal, but has a large white » 
crescent on each side of the face in front of the eye. 
FOOD HABITS. 
To determine the food habits of the blue-winged teal, 319 ° 
stomachs were examined, collected from 29 States and 4 Canadian 
Provinces during a period of 31 years, and in every month but 
January. As might be expected, the greatest numbers were col- 
lected in the fall, during the months of September, October, and 
November, making the average percentages of various kinds of foods 
for those months more accurate than for the remainder of the year. | 
Rather large series were collected in Wisconsin (58), Florida (46), 
Maine (40), and North Dakota (36); the remaining stomachs were 
fairly evenly distributed. The character of the contents of the stom- 
achs from the States furnishing the largest numbers was not such as . 
to influence unduly the final averages. 
VEGETABLE Foon. 
About seven-tenths (70.53 per cent) of the blue-winged teal’s food 
consists of vegetable matter. Of this about three-fourths is included 
in four families of plants. Sedges (Cyperaceae), with 18.79 per 
cent; pondweeds (Naiadaceae), 12.6; grasses (Gramineae), 12.26; and 
the smartweeds (Polygonaceae), 8.22. The remainder of the plant 
food is made up of algae, 2.95 per cent; waterlilies (Nymphaeaceae), 
1.37; rice and corn, 0.98; water milfoils (Haloragidaceae), 0.71; 
bur eats Eoanentiinesse), 0.38; madder family (Rubiaceae), 0.35; 
and miscellaneous, 11.92 per cam 
9 Ninety of these were examined by W. L. McAtee. 
