Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. \ 5 oe Pre i . 4 . ‘ a) - Sh 2 5 af 2 ihe ; + Pa "e Bod < ‘ : vee eee 1 " ‘ - < | - nd a aries . ‘ ag [From Annual Reports of the Department of Agriculture, 1915.] REPORT OF CHIEF OF BUREAU OF BIOLOGICAL SURVEY. Unirep Srates DerartTMENT or AGRICULTURE, Bureau or Bionocican Survey, Washington, D. C., August 31, 1915. Sir: I have the honor to submit herewith a report on the work of the Biological Survey for the fiscal year ended June 30, 1915. Respectfully, Henry W. Hensnaw, Chief, Biological Survey. Hon. D. F. Houston, Secretary of Agriculture. WORK OF THE BIOLOGICAL SURVEY. During the year the work of the Bureau of Biological Survey was conducted along four principal lines: (1) Investigations of the food habits of North American birds and mammals in relation to agri- culture, in charge of Dr. A. K. Fisher; (2) biological investigations with special reference to the geographic distribution of native animals and plants, in charge of E. W. Nelson; (3) supervision of national bird and mammal reservations, the preservation of native wild game, and the enforcement of the Lacey Act regulating the im- portation of birds and interstate shipment of game, in charge of Dr. T. S. Palmer; (4) administration of the Federal migratory-bird law, in charge of J. E. Mercer. ECONOMIC INVESTIGATIONS. FUR-BEARING ANIMALS. mestication of fur-bearing animals during the past year. The num- bers of fur bearers continue steadily to diminish as their haunts are opened up to agriculture and as they are hunted even in the most in- accessible regions. Trappers are stimulated by the high prices pelts usually command, and it becomes increasingly evident that. if the more valuable furs are to continue to serve as wearing apparel, the supply must be obtained chiefly through artificial propagation. _ Investigations of problems connected with the domestication of minks and martens were continued at Prichard, Idaho; Linden, Md.; and the National Zoological Park, and have been concerned chiefly with types of inclosures, effects of different foods on the development 9738—15 Considerable progress has been made in experiments in the do- 2 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. of young animals and growth of fur, effects of light on the color and durability of fur, molting, inbreeding, hybridizing between sub- species, importance of taming the animals, and the practical bearing” of individual temperamental differences. The results of these ex- periments are already sufficiently encouraging to warrant an exten- sion to other fur bearers, native and foreign, and the establishment in the near future of a well-equipped breeding station at some suit- able point in eastern United States having a climate requisite for producing high-grade fur. Experiments in handling and dressing pelts of the different kinds of fur bearers have been undertaken and are still in progress with a view to recommending, for those wishing to tan or dress furs, the method most satisfactory and involving the least labor and expense. A number of moleskins from the northwest coast have been secured and dressed. In size, beauty, and durability they easily surpass skins of eastern and European moles and undoubtedly are destined to become popular. Although moles are small and have such habits that it is not feasible to breed them in captivity, where they are numerous they are worthy of the attention of trappers. Investigation into the subject of silver fox farming has continued and a bulletin on the subject: will soon be ready for distribution. PRAIRIE DOG REPRESSION. Increased work was carried on in national forests and on the pub- lic domain in the extermination of prairie dogs. This work has now been practically completed in the Pike, Leadville, and Cochetopa National Forests in Colorado, the Alamo National Forest in New Mexico, the Sevier National Forest in Utah, and the Wichita Na- ‘onal Forest in Oklahoma, where more than 95 per cent of the prai- rie dogs have been destroyed and wide stretches of valuable grazing lands entirely cleared of them.* While invasion from adjacent areas is likely to occur, very little effort will be needed to keep the cleared areas free of the pest. Active campaigns against prairie dogs are being conducted on the Rio Grande Forest in Colorado, the Coconino and Sitgreaves Forests in Arizona, the Custer Forest in Montana, and the Sioux Forest in South Dakota. Important field operations and demonstrations have also been conducted in Texas, South Dakota, Oklahoma, Wyoming, Colorado, and Arizona. Oats poisoned by a process whereby the bitter taste of strychnine is largely eliminated have consistently given the best results. Usu- ally more than 85 per cent of the prairie dogs on infested areas are killed by the first application of the poisoned grain, and on the Pike, Sevier, and Wichita Forests over 95 per cent of the animals were destroyed. * The only exception to this highly successful work is the — Coconino Forest, where the abundance of a species of blue-stem — grass, of which the animals are very fond, causes the prairie dogs to care little for grain of any kind. Poisoning operations of last sum- mer in this forest were made less effective by an unusual amount of rain. and not over 70 per cent of the prairie dogs were destroyed in the poisoning and repoisoning of the areas covered. During the year the work in the field has been so systematized that for the first time , : ' 4 + tO hs BIOLOGICAL SURVEY. 3 the average cost of distributing poison on infested areas has been less than 5 cents per acre and repoisoning operations have not exceeded a cost of 3 cents per acre. GROUND SQUIRRELS ON NATIONAL FORESTS. In the California, Monterey, Sequoia, Kern, and Modoc National Forests of California, the Toiyabe Forest of Nevada, and Sopris Forest of Colorado work in controlling ground squirrels was carried on, and experimental work was conducted on the Columbia ground squirrel in Idaho. Cooperative work with the North Dakota Agri- cultural College has resulted in perfecting methods for the control of the Richardson ground squirrel, which has long been a costly pest to grain growers of North Dakota. Very successful demonstrations were made in many parts of the State. EXPERIMENTS AND DEMONSTRATIONS IN DESTROYING WOLVES. Demonstrations and experiments were carried on in Colorado, Nevada, Texas, Idaho, Oregon, and other of the Western States with a view to the control of wolves and coyotes. In eastern Oregon and northern Nevada, where rabies prevails among coyotes, careful study was made of the conditions, and a considerable number of hunters employed to assist in destroying the coyotes with a view to eradi- cating the disease. In this work the bureau cooperated with the State authorities of Oregon. The results are encouraging, and of late no new cases of rabies have been reported, and there is a very noticeable decrease in the number of coyotes. Demonstrations in Texas were very effective, and many dens were discovered and the young animals destroyed. Future work contemplates much extended activity and the division of the area inhabited by wolves and coyotes into districts, each in charge of a competent inspector, who will supervise closely the operations of trappers and hunters. z POCKET GOPHERS. Experiments in the Ochoco Forest of Oregon demonstrated the practicability of exterminating pocket gophers in National Forests. Campaigns were carried on in a number of localities within the area inhabited by these animals. JACK RABBITS. Demonstrations were carried on during the winter in Oregon, Washington, Idaho, California, Nevada, and Texas against jack rabbits, which were devastating the young orchards and forage crops, and many thousands of rabbits were destroyed. ~ MOLES. During the year an assistant of the bureau has made extensive studies of the life history of the mole inhabiting the Northwest, where moles are so abundant as to be seriously destructive in meadows 4 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. and truck gardens. Demonstrations for the purpose of informing farmers as to the best methods of controlling the pest were carried on in many parts of the region. MOUNTAIN BEAVERS. The same general region is inhabited by an animal known as the i: tain beaver” or “ sewellel,” whicl til tly, has b f mountain beaver” or “sewellel,’ which, until recently, has been o little economic importance. Lately, however, these animals have ex- tended their operations into cultivated areas and have destroyed raspberry and blackberry bushes and also farm produce. Prelimi- nary experiments for their control were conducted. 4 RE] PINE MICE. cin The pine mouse of the Eastern States, owing to the destruction of its natural enemies, has greatly increased in numbers and not only destroys seeds but feeds upon sweet potatoes and other tubers and upon the roots of fruit and shade trees. Preliminary experiments and demonstrations were made for the control of this rodent. CRAWFISH IN MISSISSIPPI. Demonstrations of methods for destroying crawfish, so injurious in Houston clay lands of Mississippi and Alabama, were continued during the year. The methods that have been worked out have proven so successful that perfect stands of cotton were secured on land that had previously been heavily infested and the crops de- stroyed by these pests. It is estimated that after the first thorough treatment lands can be kept free from crawfish at an annual ex- penditure of not to exceed 25 cents per acre. MORTALITY AMONG WILD DUCKS IN UTAH. For several successive years large numbers of wild ducks and other waterfowl around Great Salt Lake, Utah, have died, apparently from some disease, the exact cause, however, being unknown. As the destruction of waterfowl amounts annually to many thousands, the pecuniary loss is very great. During the summer of 1914 an assist- ant of the bureau carried on field investigations in the Salt Lake Valley, continuing until the end of October. Undoubtedly all the species of ducks that habitually feed in shallow water are more or less affected, but during the summer’s work only nine affected species came under observation. The loss among them was very great. In 1912 nearly 45,000 dead ducks were picked up on one marsh. It is of interest to note that the fatality is by no means confined to ducks, but includes many species belonging to widely different fam- ilies, as grebes, herons, shorebirds, avocets, and stilts. The trouble during the present year began in July and terminated about Sep- tember 20. The birds affected seem partially paralyzed, losing the power of flight, and gradually weakening until they die. The first clue to the nature of the trouble was obtained when it was found that affected ducks generally recover readily when given fresh water, and of 586 so treated in experimental pens 426 were entirely cured. BIOLOGICAL SURVEY. 5 ‘Further experiments and observations seem to prove beyond a rea- sonable doubt that the trouble arises from the presence in the water of an alkali that is absorbed through the alimentary canal in fatal quantities. Tt was ascertained that a similar trouble exists at Tulare Lake, Cal., and results there also in the death of many waterfowl. An assistant engaged in the work visited this locality in November in order to study local conditions. A report on the progress made was published in May. DESTRUCTION OF OYSTERS BY CERTAIN WILD DUCKS. Examination of stomachs of wild ducks secured from near Olym- pia, Wash., definitely supported a charge that certain scaups and scoters were doing considerable damage locally to oyster beds. Dur- ing the ducking season of 1914-15 inv vestigations were carried on by an assistant of the Survey on the headwaters of Puget Sound and the whole of Willapa Harbor, and noteworthy damage was found to be confined to a single bay—Oyster Bay—18 miles northwest of Olympia, Wash. Two species of ducks—the greater scaup, or bluebill, and the white-winged scoter, or coot—were found to be doing all the damage. The average numbers of these birds present on Oyster Bay during the season were 2,000 and 300, respectively. An estimate (subject to revision) was made that these ducks were destroying about 8,000 oysters daily, the money value of which would be $20. This would amount to about $3,600 for the duck season. Effective measures for relief are in force. FOOD OF WILD DUCKS. The work of the bureau in acquiring and disseminating informa- tion regarding the propagation of plants best suited for wild-fowl food has been greatly appreciated by game protective associations and individuals interested in the preservation and propagation of native wild fowl. In response to requests for information of this nature, a third publication in the series on important wild-duck foods was issued in May. This bulletin treats of 11 groups of plants, in- cluding 2 fresh-water plants of wide distribution in the United States; 2 2 of more southerly range; 2 trees of southern swamps whose abundant seeds are eagerly eaten by ducks; 1 strictly salt-water duck food, the first thus far recommended by the bureau; 1 brackish-water plant: and 3 others of such luxuriant growth as to be especially adapted for use on duck farms. THE EUROPEAN STARLING. The European starling, an introduced species, continues to increase in numbers and to occupy new territory. Reports of the bird’s activities are somewhat conflicting. That it is to some extent bene- ficial is proven by its destruction of insects, especially in summer. In some localities, however, it is charged with the destruction of small fruit, and unquestionably its presence in numbers is inimical 6 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. to our native species that build in tree cavities and boxes, as wrens, martins, swallows, and flickers; and with these it is brought into direct competition. A circular has been widely distributed for the purpose of eliciting information as to the extent of territory the starling now inhabits and as to the amount of damage the bird inflicts on fruit. Information on the economic importance of the bird has been sought during the year by means of letters and by the collection of stomachs. It is planned to carry on field investigations of the star- ling as soon as possible with a view to determining its status in the _ United States. ATTRACTING BIRDS. Bird lovers throughout the land are seeking ways and means of increasing the number of birds and of attracting them to the vicinity of homes. While the basis for this movement is in part esthetic, to no small degree such efforts are based on a growing appreciation of the usefulness of birds as insect destroyers. The increase of interest in wild birds throughout the United States during the past decade has been phenomenal, and organizations having for their chief object the care and protection of birds are numbered by hundreds, if not thousands. Civic leagues and women’s clubs have been especially active in attempts to attract birds to city parks and suburbs, with a view to bringing wild life to the doors of those denied the privilege of knowing it in wilder districts. Two publications issued during the year designed to aid and advance this movement—“Bird Houses and How to Build Them” and “ How to Attract Birds in North- eastern United States ”—constitute manuals on the means of attract- ing birds and fill a widespread and continually growing demand. The bulletin discussing methods of attracting birds is the first of a series planned to cover all sections of the United States. Special attention is given to the kinds of fruit-bearing shrubs and trees important as furnishing food for birds. ECONOMIC STATUS OF CERTAIN IMPORTANT SPECIES. Examination of bird stomachs by groups was completed for mal- lards, wrens, thrashers, mocking birds, catbirds, chickadees, and tit- mice. In the case of cuckoos, crows, and jays the examinations were brought up to date. Intensive study of the common crow is being made with a view to supplying precise information as to its economic status. In a publication issued in July on birds in relation to the alfalfa weevil it was shown that 45 species of birds prey upon this pest. Economic investigations of food habits of birds resulted in a bulletin on the food of the robins and bluebirds of the United States, and a revision, under the title “Some Common Birds Useful to the Farmer,” of an earlier Farmers’ Bulletin (No. 54) which has had a larger circulation than any other publication on American birds. Reports on the food habits of thrushes of the United States, on the birds of Porto Rico, and on some common birds of southeastern United States will soon be published. BIOLOGICAL SURVEY. | BIOLOGICAL INVESTIGATIONS. Biological investigations have been mainly along lines which sup- ply information essential to the effective administration of the vari- cus activities of the bureau, including the enforcement of the Lacey Act regulating importaticn and shipment of game, the Federal mi- gratory-bird law, maintenance of bird and mammal reservations, and economic investigations concerning the relations of birds and mam- mals to agriculture, stock-growing, and forestry. In securing in- formation:of practical value in connection with the conservation of cur bird and mammal life, particularly in regard to the species of economic importance, a card-index file, consisting largely of unpub- lished data gathered by the field parties of the bureau, has been greatly increased. Manuscript field notes on mammals gathered dur- ing the past 25 years have been arranged in the card files, and for the first time have become readily available for reference. The files concerning North American birds now contain more than 1,000,000 cards. DISTRIBUTION AND MIGRATION OF BIRDS. Regular reports on the migration of birds have been received dur- ing the year from all parts of the United States from more than 300 volunteer observers and some from Canada and Alaska. These furnish invaluable records in connection with the administration of the migratory-bird Jaw. Office investigation has included the colla- tion 4nd preparation for publication of material concerning the distribution and migration of gulls, terns, and rails and their allies and several other groups of birds. As rapidly as possible facts gathered in investigations of bird migration are being published that the information may he available for the use of those interested, par- ticularly in connection with the formulation of laws for the protec- . tion of birds by the various States. BIRD CENSUS. The data secured by the first bird census, made in the spring of 1914, were studied and a preliminary report prepared and published. The results proved of extreme interest and showed the possibility of largely increasing the bird life throughout the country. A second national bird census was announced for the spring of 1915, and more than 200 voluntary observers took part in it, covering the country more generally than in the preceding year. The results of this work also will be prepared for publication. One of the most valuable facts developed by the bird census was that where an effort is made to pro- tect birds from their enemies there is a notable increase of the bird population. DISTRIBUTION MAPS OF BIRDS AND MAMMALS. _ Work was continued on the preparation of distribution maps show- ing the area occupied by each species of bird and mammal in North America.