GNATCATCHERS. 91 



at 3.20 p. m., and the following hour the young were fed 8 times, 

 and as the weather w^as cold the mother bird spent a number of min- 

 utes on the nest Avarming the nestlings. On July 1 another hour was 

 spent in watching the nest, beginning at 9.30 a. m., and only 4 feed- 

 ings were observed. It was, however, a cold, windy morning, and 

 one or other of the parent birds remained on the nest all the time, 

 leaving only when the mate brought food and took its turn brooding. 

 The necessity for keeping the nestlings warm evidently prevented the 

 parents from feeding them as often as customary. On the morning 

 of July 3, although the weather was still rather cool, the birds 

 seemed to be making up for the scanty feeding of the previous days, 

 for they were observed to feed the young 15 times in an hour, begin- 

 ning at 9.40 a. m., although they still took turns in warming the 

 young for a few minutes at a time. In the afternoon of the same day, 

 beginning at 4 o'clock, 8 feedings were noted in an hour. On July 5, 

 beginning at 10 a. m., the parents were seen to feed the nestlings no 

 fewer than 18 times, although one of them spent several minutes 

 upon the nest three times during the hour. In the afternoon of that 

 day 11 feedings were noted, in the hour beginning at 3.30, and 3 

 times one of the parents brooded the young, remaining once for six 

 minutes. The next observation on this nest was made on July 6, 

 during the hour from 7.50 a. m., and 12 feedings w^ere noted. On 

 July 7 the last observation was made, beginning at 3.20 p. m., and 11 

 feedings were noted. In this case there were 87 feedings in eight 

 hours, or an average of nearly 11 per hour. 



Considering both nests together, as each had the same number of 

 young, we have 144 feedings in fourteen hours. Now at this time of 

 year there are just about fourteen hours of available daylight, so that 

 144 feedings may be considered as an average day's work for a pair 

 of parent birds, and as signifying the destruction of at least 144 

 insects, probablj^ several times that number. Each of the three 

 young must have been fed 48 times, which means that each stomach 

 was filled to its full cajDacity several times during the day, another 

 illustration of the fact that the digestion and assimilation of birds, 

 especially of young ones, is constant and very rapid. This is further 

 shown by the fact that when attempts have been made to raise young 

 birds the experiments in most cases have failed because the nestlings 

 were not fed often enough and actually starved to death. Young 

 birds thrive best when fed a small quantity of food at short intervals 

 rather than greater quantities at longer periods. 



SUMMARY. 



From the foregoing it appears that although this thrush eats con- 

 siderable fruit it is not a pest lo the fruit grower. Cherries seem to 



