Bulletin of the of Agriculture . rably morefood. The elements of the diet of nestlings are essentially the same asthose of adults, though the relative percentages differ food habits of the nestlings themselves also vary from the periodwhen, a day or two old, their tender-walled stomachs require such soft, 1 Forbush, E. H„ Useful Birds and Their Protection, p. 47, 1907. 56 BULLETIN 621, U. S. DEPARTMENT OF AGRICULTURE. digestible food as spiders and caterpillars, to the time when, fullyfledged, they relish hard-shelled beetles, crustaceans, small mammals,and grain
Bulletin of the of Agriculture . rably morefood. The elements of the diet of nestlings are essentially the same asthose of adults, though the relative percentages differ food habits of the nestlings themselves also vary from the periodwhen, a day or two old, their tender-walled stomachs require such soft, 1 Forbush, E. H„ Useful Birds and Their Protection, p. 47, 1907. 56 BULLETIN 621, U. S. DEPARTMENT OF AGRICULTURE. digestible food as spiders and caterpillars, to the time when, fullyfledged, they relish hard-shelled beetles, crustaceans, small mammals,and grain, a diet differing but slightly from that of the parents. Theseries of stomachs examined includes young of all ages, and, as thevarious stages of growth are about equally represented numerically,the percentages derived may be considered as approximately a trueaverage for the nestling. A diagrammatic representation of the foodof these young birds is presented in figure 3 and a tabular statementshowing percentages is given in , Fig. 3.—Food of nestling crows. The proportions of the various elements are representedby the relative sizes of the different sectors. Table IV presents the same informationin percentages. Table IV.—Percentages of the principal food items of the nestling crow. A Jh B 3 . o -o t3 fl Fl to ©3 — ?Q ftftO o . 03 T3 g AS 03 03 S^ 1 o 03 3g o si ?3 j> W> to a. a o 03 o .2 ©3 03 3 = ou o IV o O 603 m ft o I feG 2 &ft 9 td1 c3 3 ftr3£ fl 2 a H3 03 U 60 o a ® o o floO ° ® S 4 58 THE CROW AND ITS RELATION TO MAN. 57 Animal Food. Animal food comprised per cent of the diet of the nestlingcrows examined, insects forming the major portion, per half of this, per cent, was composed of beetles, slightlyless than the corresponding percentage in the diet of adults duringMay. Coleoptera. ScARABiEiDiE.—Scarabaeid beetles, m
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectagriculture, bookyear
