WARBLEBRS. 49 
Vegetable food—The vegetable portion is only about 23 percent. 
Nearly all of this was fruit pulp contained in a single stomach. 
This, with one or two seeds and a few accidental bits of rubbish, 
makes up the whole vegetable contingent, which, therefore, may be dis- 
missed without further comment. 
FOOD OF NESTLINGS. 
Some idea of the amount of insect food eaten by warblers may be 
obtained by watching the feeding of their young by the parent birds. 
A nest of the summer warbler containing two young, about a week 
old when discovered, was watched for six hours distributed over three 
days. The nest was situated in a prune tree in an orchard, and it is 
practically certain that all the food for this family was obtained in 
the orchard. The results of the observation appear in the following 
table: 
Forenoon. Afternoon. 
Date. | fetes toed 
Hour of obser- eas Hour of obser- Number 
| vation. ings. vation. ings. 
t 
TUIMO ID one ahi ciesnceieieeieiall sicreeiecietate 3. 26-4. 26 21 
June 14 8. 21- 9.21 OL ossescuagiansacenl atest ee 
June 14 10, 34-11.34 32 4. 36-5. 36 31 
June 15 8.00- 9.00 36 1,11-2.11 30 
In six hours 181 feedings were observed, an average of 304 per 
hour. As there were only two young, it follows that each nestling 
was fed 15 times per hour, or for a day of fourteen hours 210 times. 
Both parent birds took part in feeding the young, but it was noted 
that the female visited the nest most frequently. 
SUM MARY. 
From the above facts it is evident that the presence of a few 
warbler nests in an orchard goes far to safeguard the trees from 
attacks of insect enemies. The inference is plain that the presence 
of insectivorous birds should be encouraged by the orchardist by 
every means in his power. The summer warbler is, if possible, even 
more completely beneficial in its food habits than the Audubon 
warbler. Its animal food in relation to man is almost entirely nox- 
ious or neutral, and it eats so little vegetable food that its character 1 is 
of but Slight consequence. : 
WESTERN YELLOWTHROAT. 
(Geothlypis trichas subspp.) 
In California the yellowthroat is an inhabitant of marshes and low, 
bushy places among tules or willows. While it is an insect eater of 
9879—No. 30—-07—4. 
