Food Habits of the Thrushes of the United States

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Beal Foster Ellenborough Lascelles. Food Habits of the Thrushes of the United States

INTRODUCTION

TOWNSEND'S SOLITAIRE

WOOD THRUSH

VEERY AND WILLOW THRUSH

GRAY-CHEEKED AND BICKNELL'S THRUSHES

OLIVE-BACKED AND RUSSET-BACKED THRUSHES

HERMIT THRUSHES

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Townsend's solitaire, a bird of the far West, is a resident of high mountains and lonely gorges. It is partial to running streams and often builds its nest just above a rushing mountain torrent. It ranges from Alaska through the Sierras south to San Bernardino, Cal., and through the Rockies to Arizona and New Mexico, and occasionally farther east. The species is not evenly distributed over this region, but is restricted to such high mountainous portions as afford its favorite surroundings. As long as it retains these habits the bird will have little or no effect upon the products of husbandry, and its food can have only a scientific interest. The song of this species is said to be at times the finest of any of the thrush family.

As this bird is comparatively rare in settled regions only 41 stomachs are available for determining the character of its food. The most southerly and easterly one was taken in Texas, the most westerly in California, and the most northerly in Wyoming. They are distributed through all the months of the year, although April and May are represented by but one each and December by but two. Every other month has three or more. An investigation based upon such limited material can be considered only as preliminary, but will serve to show some of the more important elements of the food. This was made up of 35.90 per cent of animal matter to 64.10 of vegetable.

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Lepidoptera (caterpillars) make the largest item in the food of Myadestes. Eaten much more regularly than beetles, they probably are a standard article of diet. They were found in the stomachs collected in every month of the year but four, and a greater number of stomachs would probably show them in every month. The one stomach taken in May contained the maximum (72 per cent). The total for the year is 12.95 per cent. Ants are eaten to the extent of 4.71 per cent, while other Hymenoptera, as bees and wasps, make up less than half of 1 per cent. Diptera (flies) are represented by a mere trace in the stomachs. Observers who have seen this bird in its native haunts testify that it takes a considerable portion of its food on the wing. In view of this fact it seems curious that the two orders of insects most active on the wing (Hymenoptera and Diptera) should be so scantily represented in the food. Hymenoptera are a standard diet with flycatchers and would seem to be the natural food of any bird that feeds upon the wing.

Hemiptera (bugs) were found to the extent of 3.51 per cent of the total food. All were contained in three stomachs taken in March, June, and July. In the July stomach four cicadas, or dog-day flies, constituted the whole contents. Grasshoppers amount to less than 1 per cent and all other insects to but a trifle. Spiders were eaten to the extent of 2.94 per cent of the food and were found in the stomachs taken in seven of the twelve months, and judging from their distribution they are eaten whenever available. A hair snake (Gordius) was found in one stomach. Following is a list of insects identified and the number of stomachs in which found:

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