446 University of California Publications in Zoology [VOL. 11 

 INDICES OF AVAILABILITY OF COMMON INSECTS EATEN BY WESTERN MEADOWLARKS 



No. of Cut- Grass- Bees and 



Locality birds Beetles worms hoppers Crickets Bugs wasps Ants 



Live Oak, gutter Co. 60 1,775 288 2,162 4 533 78 18 



Hollister, San Benita Co. 60 4,307 7 1,492 6,680 197 265 35 



The most available and the most popular food of the western 

 meadowlark, if it may be judged by the frequency with which 

 it has been found in the stomachs, is beetles. Seventy-five per 

 cent of all the stomachs examined contained beetles (Coleoptera). 

 Vegetable food in the form of oats is next in order of frequency, 

 thirty-four per cent of the meadowlarks examined having taken 

 oats as food. Grasshoppers, cutworms and caterpillars, and weed 

 seeds were found in thirty per cent, twenty-six per cent, and 

 twenty-five per cent respectively of the stomachs examined. 



The accompanying table gives a summary of the number of 

 times each article of diet was taken and the percentage of each 

 article in the diet of the species. Attention should be called 

 to the fact that a very large percentage (seventy per cent) of 

 the birds taking oats took wild oats (Avena fatua) instead of 

 the tame varieties. Consequently not more than ten per cent 

 of the birds examined had taken cultivated varieties of oats. 



Although the percentages showing the proportionate number 

 of times each kind of food is taken to the number of birds exam- 

 ined differs from the percentages showing the proportionate vol- 

 ume of each kind of food, yet they parallel each other to a 

 considerable extent. The accompanying table, giving only th^ 

 principal articles of diet, shows this parallelism in the per- 

 centages. 



IV. PERCENTAGE-VOLUME AND PERCENTAGE OF WESTERN MEADOWLARKS TAKING DIFFERENT 



ELEMENTS OF FOOD 



1 II * ! 



03 03 ,J3 CO Q, 



11 I S I ii 35 



6 & ~ 6 5 "" <d pr ^ t"" 



Percentage-volume ... 30.1 9.9 17.0 3.5 18.0 3.1 3.0 4.0 .1 

 Percentage of birds 



taking 46.0 25.0 75.2 12.4 30.5 13.4 16.7 19.2 1.1 



