88 



THE WINTER FOOD OF THE CHICKADEE 



as to its identity. Another larva commonly found was one 

 which winters over on the twigs in a small silken case, as 

 shown in the light spots in Fig. 8. The bark beetles of the 

 family Scolytidce, which are destruct- 

 ive to forests all over our country, were 

 also freely eaten by the chickadees. 

 Some birds which had passed through 

 the pine woods of the College farm were 

 found to have eaten many of these bee- 

 tles, the precise species being deter- 

 mined by Mr. E. A. Swarz of the 

 United States Department of Agricul- 

 ture, as Pityogenes sparsus Lec. So 

 much of the time of these birds is spent 

 in the woods that it is evident that 

 they are of great benefit in destroying 

 bark-beetles and other pests of forest 

 trees. 



The hairy skins of the fruit of the 

 common, wild sumachs were among the 

 most abundant elements of the vegeta- 

 ble food present. The edible portion 

 Fig. 4. Egg-mass of Amei- of these fruits is evidently eaten to a 

 icanTentCaterpillar. considerable extent throughout the win- 



(These eggs are eaten by 

 Chickadees.) ■ 'S''- 



The Results in Detail 



On the assumption that the scientific details of this study of 

 the chickadee's food will not be of especial interest to the gen- 

 eral reader, the following records are printed in smaller type, 

 and may be passed over by any one who cares only for the gen- 

 eral results. 



But one specimen taken in November (the 12th) was studied. It 

 had been killed after a tour through the tops of the pines in the Col- 

 lege woods, and the stomach was chiefly filled with the fragments of 

 small beetles belonging to the family of bark beetles (Scolytidce). 

 These were estimated to form 85 per cent, of the entire contents. 

 There were also five large eggs of an insect which were identified by 



THE winter food OF THE CHICKADEE 89 



Dr. L. O. Howard as belonging to some species of the family Reduvii- 

 dcB, making 2 per cent. ; three small larvse, apparently of the order 

 Diptera, I per cent.; fragments of sumach berries, 2 per cent., and 

 undetermined material, lo per cent. 



The next specimen was taken De- 

 cember gth in an apple tree, it having 

 previously been followed through a 

 mixed growth of young pines, maple, 

 willow, and birches. The stomach 

 was nearly full of the eggs of aphides, 

 429 of these being counted in the 

 mass ; they were estimated to form 70 

 per cent, of the stomach contents. 

 There were also present a small moth, 

 4 per cent. ; a Carabid beetie, 5 per 

 cent. ; a snout beetle, 4 per cent. ; 

 two insect larvae, 4 per cent. ; an egg 

 of the fall canker worm, i per cent. ; 

 feathers a trace, and undetermined 

 material, i per cent. 



The first specimens collected in Jan- 

 uary were taken on the igth at 2 p. m., 

 and consisted of four birds which had 

 just passed through a young growth 

 of grey birches, apple and maple trees 

 growing in a neglected pasture. Three 

 of these had eaten largely of vegetable 

 matter which was doubtfully identified 

 as the buds of some small plant ; this 

 material constituted 70 per cent, in 

 two of the specimens and 75 per cent, 

 in the third. The first bird had eaten 

 in addition the following: Three in- 

 sect larv£B, I per cent. ; about 45 in- 

 sect eggs, 5 per cent. ; undetermined fig, 5. Eggs of Fall Canker Worm 

 insects, 2 per cent. ; small seeds, 6 on Elm Twig. (Chickadees feed 

 per cent. ; undetermined material, 8 ft-eely on these Eggs.) 

 per cent. The second specimen had 



a somewhat similar record, except that 6 per cent, of aphid eggs had 

 been eaten. The third had eaten a large geometrid larva, forming 5 per 

 cent of the food. The fourth chickadee of this lot had partaken of a 

 somewhat different food from the other three. The principal item in 

 its bill of fare consisted of material which was believed to be the skins 

 of apples hanging from the trees, making 40 per cent, of the total 

 food; plant-lice eggs formed 6 per cent.; eggs of fall canker worm, 4 

 per cent. ; a lepidopterous larva, 10 per cent. ; a large bud of a decid- 

 uous tree or shrub, 8 per cent. ; small buds, 6 per cent. ; and material 

 not determined, 26 per cent. 



Two chickadees were taken in Durham among some grey birches on 

 the banks of the Oyster River at 10 a. m., February 14th. Both had 



