154 BULLETIN 17 6, UNITED STATES NATIONAL MUSEUM 



Seventy percent of the total food among the wood warblers ! How- 

 ever, it seems also to be a most exceptional case, for nothing that even 

 approaches it is found in the list below, which embraces a range of 

 45 stomachs from five States and one Canadian Province. The entire 

 amount of the stomachs listed contained the remains of but two birds ! 



With reference to the Oklahoma stomach, I wonder whether there 

 might be a seasonal variation in the bird-taking propensities of the 

 chuck-will's-widow in relation to migration. It would appear rea- 

 sonable to believe that when there is high activity among birds trav- 

 eling through a given area, such as would take place in the spring 

 migration, the chucks of that locality would have greater opportunity 

 in securing them. One would not have to incline to the predatory 

 theory to accept this, for if there are a great many small birds passing 

 through an area for a few weeks, the chucks in their night hunting 

 would blunder across more birds than would be the case later in the 

 season. If the take is accidental, a higher percentage of accidents 

 would then occur. If, on the other hand, the take is deliberate, then 

 the chances of indulging that habit would be greater and would fall 

 off later in the season. So, whatever impulse governs the matter, the 

 migrations would result in more birds appearing in the diet. Un- 

 fortunately, the Oklahoma stomach was undated, so it is impossible 

 to ascertain whether the bird secured its high percentage during a 

 migration or not, but I incline to the belief that it was a spring 

 specimen. 



To return to the analysis. Miss Knappen states : "The other 45 stom- 

 achs taken in March (2), April (31), May (11), and November (1) 

 were collected in Florida (37), Georgia (1), Mississippi (2), North 

 Carolina (1), Ontario (1), and Texas (3). The annual percentages 

 of different items in the food, which was entirely animal, equal: 

 Carabidae, 3.64; Phyllophaga^ 32.98; other Scarabaeidae, 25.28; 

 Cerambycidae, 4.49 ; Elateridae, 1.34 ; other Coleoptera, 5.13 ; Lepidop- 

 tera (moths), 12.36; Odonata, 4.63; Aves, 7.21; and miscellaneous 

 animals, 2.85. 



"The genera most persistently eaten were Phyllophaga (May 

 beetles) and Anomala. The birds consumed were 1 Dendroica pal- 

 marum and 1 HelTninthophUa sp., while the miscellaneous bracjiet 

 includes various bugs, flies, a bivalve, and other animal material." 



The insect content of these 45 stomachs totals more than 70 percent 

 in but three classes {Phyllophaga^ Scarabaeidae, and Lepidoptera) 

 and other kinds make up considerably more than that. Birds are 

 represented by only 7.21 percent, and both victims were warblers. 

 One cannot but wonder at the single "bivalve," an item that would 

 certainly not occur to most students as being connected with a 

 chuck's diet. 



