the food. While there is no doubt that a considerable quantity of this is waste, still a very decided taste for grain is shown, a point that is more especially emphasized by the large quantity (more than 54 percent of the total food) eaten in August: Corn, from its appearance in such large quantities in the food of the early spring months, is evidently picked up as waste grain to a considerable extent, but oats and wheat, which appear at the same time, are probably largely taken from newly sown fields. In July and August they evidently come from harvest fields. Mr. E. W. Nelson, of the Biological Survey, informs the writer that from about the last of August to the end of September the cornfields of the table-lands of Mexico are much damaged by yellowheads. Weed seed appears as a very prominent item of food in every one of the seven months under consideration, except October, the record for which is based on only 3 stomachs and hence can not be made a basis for sound conclusions. Beginning with 18 percent in April, it increases to 34 percent in June, drops to 6.6 in July (to make room for caterpillars and grasshoppers), rises to 36.1 percent in August, and finally to 64.4 percent in September. While, as stated above, none was found in the 3 October stomachs, there is no reason to doubt that weed seed is not only a common article of food in that month but also a staple diet in the other colder months of the year. It is to be regretted that no stomachs of the yellowhead have been received from its winter range, to give some idea of its food during the colder season. It is almost certain, however, that this would be found to consist of weed seed and waste grain, as in the case of its neighbor, the redwing. The weeds found in the stomachs are almost precisely the same as those eaten by the redwings, and in practically the same proportions. Barngrass (Chatochloa), Panicum, and ragweed (Ambrosia) are the leading kinds, supplemented by Polygonum, Rumex, and others. SUMMARY. From this brief review some conclusions may be drawn, but the somewhat fragmentary nature of the evidence makes it probable that they may be subject to considerable modification in future. It is almost certain that the rather peculiar distribution of the various items of food through the season will prove to be more apparent than real in the light of more extensive observations. In the meantime we may safely conclude (1) that the yellowhead feeds principally upon insects, grain, and weed seed, and does not attack fruit or garden produce; (2) that it does much good by eating noxious insects and troublesome weeds, and (3) that where too abundant it is likely to be injurious to grain. When it is considered that the redwing has been accused of doing immense damage to grainfields, it is evident that the yellowhead, which has been found to eat nearly three times as much grain as the former, must be capable of much mischief in localities where it becomes superabundant. The following table shows the various elements of the food for each month of the season: Food of the yellow-headed blackbird. [NUMBER OF STOMACHS EXAMINED: April, 9; May, 31; June, 14; July, 16; August, 60; September, 5 October, 3; total, 138.] The red-winged blackbird (otherwise known as the red-shouldered blackbird, swamp blackbird, and American starling), including its various races,' inhabits North America from Nova Scotia and Great Slave Lake south to Costa Rica. It breeds throughout its range in the United States and Canada. The typical form is replaced at different places in the southern part of the range by the Bahama, Florida, and Sonoran redwings, but the differences that separate these various subspecies are scarcely appreciable by the casual observer. The bird is curiously restricted in its local distribution by the fact that it nests as a rule only in the immediate vicinity of water, and preferably directly over it. For this reason it is absent from extensive tracts of country either in high mountainous regions or in desert or forest areas. Nests have occasionally been found in perfectly dry situations at a distance from water, but such cases are exceptional. The prairies of the Upper Mississippi Valley, with their numerous sloughs and ponds, furnish ideal nesting places for redwings, and consequently this region has become the great breeding ground for the 'The different subspecies are not considered separately in this bulletin. species. In many places, especially on the borders of shallow lakes, thousands of acres of rushes and reeds of various kinds afford nesting sites for redwings, yellowheads, and marsh wrens, while myriads of more aquatic species swim in the waters below and nest amid the broken herbage. It is from such breeding grounds that the vast flocks are recruited that make such havoc upon fields of grain and call forth the maledictions of the unfortunate farmer. East of the Appalachian Range the conditions are different. Marshes on the shores of lakes, rivers, and estuaries are here the only sites available for breeding purposes, and as these are more restricted in number and area than the western breeding grounds the species is much less abundant than in the West. Like their associates, the marsh wrens, and their neighbors, the bank swallows, the redwings are eminently gregarious, living in flocks for the greater part of the time and breeding in communities which vary in size according to the area of the swamp they occupy. Sometimes these colonies are reduced to a single family, which in such cases usually consists of one male bird with several females and their nests; for this species practices polygamy, a habit noted in the case of only a few species of song birds. During the winter the redwings are in the South, but may occasionally be found as far north as latitude 40°, and stragglers may occur at any point within their summer range. (A young male was shot by the writer in central Iowa in January, 1879, and one bird whose stomach appear is included in this investigation was killed in northern Massachusetts on January 29, 1896.) In their northward migration they begin to in the Upper Mississippi Valley about the last of February or during the first half of March, and by the middle of March enter the New England States. On the return journey they begin to leave the more northern portions of their range in September, and the migration is practically complete by the end of October. Although they arrive from the South at an early date, they are by no means early breeders, for at that time the marshes are desolate wastes of dead and broken-down herbage, and the birds do not build until the new growth is considerably advanced. This involves a delay of several weeks, during which the birds, having taken possession of a marsh where they intend to construct their homes, sit idly about and behave as though time hung heavily upon them. The females usually perch upon the dead vegetation as if watching for the new growth to appear, while their liege lord, with the resplendent insignia of his rank conspicuous on his shoulders, struts about upon some fence or tree and swells his little body, ruffles up his feathers, and by a display of his brilliant colors and a rather poor attempt at singing tries to make the time less wearisome to his patient mates. Owing to their peculiar nesting habits these birds do not come in contact with the farmers' crops appreciably during the breeding season, since at this time they confine themselves to the immediate vicinity of their marshy homes. After the season of reproduction they assemble in flocks, usually of a considerable size and often immense, and it is at this time that they frequently do serious harm to crops of standing grain. Much testimony has been received by the Department of Agriculture indicating that the damage is sometimes enormous. In letters received from the rice growers in the South the redwing is implicated equally with the bobolink in destroying rice both in spring and fall. It is claimed by some, however, that the redwing is not wholly bad, as it remains in the fields during the winter and eats the volunteer' rice, which, if it grew in any considerable quantity, would spoil the crop. 6 On the other hand, there is considerable evidence that redwings eat a great many insects, and that it is only under exceptional circumstances that they eat grain to an injurious extent. It is noticeable that nearly all complaints against them come from the Mississippi Valley, where the native grasses and weeds of the prairies have been replaced by vast fields of grain. It has also been stated that the greatest damage was done when but few fields of grain had been planted. These afforded a new and easily accessible supply of food of which the birds were not slow to avail themselves; but since the grainfields have increased in area the work of the birds has become more widely distributed, and the damage has not been so apparent. Wilson, in speaking of the food of the redwing, says: * * * The whole season of winter, that, with most birds, is passed in struggling to sustain life in silent melancholy, is, with the redwings, one continued carnival. The profuse gleanings of the old rice, corn, and buckwheat fields, supply them with abundant food, at once ready and nutritious. Before the beginning of September, these flocks have become numerous and formidable; and the young ears of maize, or Indian corn, being then in their soft, succulent, milky state, present a temptation that can not be resisted. Reenforced by numerous and daily flocks from all parts of the interior, they pour down on the low countries in prodigious multitudes. Here they are seen, like vast clouds, wheeling and driving over the meadows and devoted cornfields, darkening the air with their numbers. Then commences the work of destruction on the corn, the husks of which, * * are soon completely or partially torn off; while from all quarters myriads continue to pour down like a tempest, blackening half an acre at a time; and, if not disturbed, repeat their depredations till little remains but the cob and the shriveled skins of the grain; what little is left of the tender ear, being exposed to the rains and weather, is generally much injured. * * * * * * * It has been already stated, that they arrive in Pennsylvania late in March. Their general food at this season, as well as during the early part of summer, consists of grubworms, caterpillars, and various other larvæ, the silent, but deadly enemies of all vegetation, and whose secret and insidious attacks are more to be dreaded by the husbandman than the combined forces of the whole feathered tribes together. For these vermin, the starlings search with great diligence; in the ground, at the roots of plants, in orchards, and meadows, as well as among buds, leaves, and blossoms; and from their known voracity, the multitudes of these insects which they destroy must be immense. Let me illustrate this by a short computation: If we suppose each bird, on an average, to devour fifty of these larvæ in a day, (a very moderate allowance,) a single pair, in four months, the usual time such food is sought after, will consume upward of twelve thousand. It is believed, that not less than a million pair of these birds are distributed over the whole extent of the United States in summer; whose food, being nearly the same, would swell the amount of vermin destroyed to twelve thousand millions. But the number of young birds may be fairly estimated at double that of their parents; and, as these are constantly fed on larvæ for at least three weeks, making only the same allowance for them as for the old ones, their share would amount to four thousand two hundred millions; making a grand total of sixteen thousand two hundred millions of noxious insects destroyed in the space of four months by this single species! The combined ravages of such a hideous host of vermin would be sufficient to spread famine and desolation over a wide extent of the richest and best cultivated country on earth. All this, it may be said, is mere supposition. It is, however, supposition founded on known and acknowledged facts. I have never dissected any of these birds in spring without receiving the most striking and satisfactory proofs of these facts; and though, in a matter of this kind, it is impossible to ascertain precisely the amount of the benefits derived by agriculture from this, and many other species of our birds, yet, in the present case, I can not resist the belief, that the services of this species, in spring, are far more important and beneficial than the value of all that portion of corn which a careful and active farmer permits himself to lose by it.1 Audubon, in speaking of this species, says: The marsh blackbird is so well known as being a bird of the most nefarious propensities, that in the United States one can hardly mention its name, without hearing such an account of its pilferings as might induce the young student of nature to conceive that it had been created for the purpose of annoying the farmer. That it 1 1 Am. Ornith., Edinburgh ed., Vol. I., pp. 193-198, 1831. |