I9li] Bryant: Economic Status of the Western Mcacloirlark 459 



had fed upon the larvae or pupae. However, any increased de- 

 struction at the time when insects appear in abnormal numbers 

 must be considered a benefit. 



Four out of the five bird.s found to feed on the butterflies 

 are numbered among the birds whose usual food habits justly 

 subject them to severe criticism from the farmer. Consequently 

 the conclusion can be drawn that some of the birds noted for 

 their depredations often become valuable insect destroyers at just 

 the time when they are most needed as such. 



This evidence fails to support Mr. McAtee's contention that 

 "butterflies are in very little demand with birds in tlie United 

 States." Not, on the other hand, does it support the conclusions 

 of Finn (1897) that "there is a general appetite for butterflies 

 among insectivorous birds, even though they are rarely seen when 

 wild to attack them." Middle ground seenis to be the best 

 position to assume until more evidence is at hand. 



In our attempt to explain why butterflies are seldom taken 

 by birds we have laid emphasis on palatability. This factor can 

 at best be but one of many factors, many of which are perhaps 

 just as important if not more important. Then, too, it should 

 be noted that palatability is an extremely variable factor, for 

 it varies with the species, the time of year, the availability of 

 food, etc. We still need a full examination of all of the factors 

 governing the food-taking of birds in order to explain the inter- 

 relation between birds and butterflies. 



In an investigation of a grasshopper outbreak at Los Banos. 

 Merced County, in July, 1912, it was found that western meadow- 

 larks were destroying an average of nearly fifty grasshoppers a 

 day. From point of numbers and average number of grasshop- 

 pers destroyed, the western meadowlark was. next to the hi colored 

 red-wing, the most efficient destroyer of the pests. IMeadowlarks 

 averaged more grasshoppers per bird and were outdone by the 

 red-wings only when the numbers of individual birds and the 

 total destruction accomplished by each species were considered. 



A comparison of the food of meadowlarks taken in the same 

 locality in 1911, when grasshoppers were not so abundant as they 

 were in 1912, demonstrated the fact that meadowlarks averaged 

 more grasshoppers when these insects were abnormally abundant 



