of our most valuable species, as bluebirds, swallows, wrens, and woodpeckers. When put up near the farmhouse these not only serve to attract birds and provide for their increase, but add much to the interest and pleasure of the household. The making of artificial nesting boxes has become an established industry in Germany, where the need of increased numbers of insectivorous birds for the protection of the forests was clearly perceived, and they are beginning to be put on the market in this country.

(2) By planting thickets of berry-bearing trees and shrubs along the roads or in waste places on the farm, which will provide not only food but also nesting places and refuge resorts from nocturnal enemies of the birds. On many farms it is necessary only to preserve and encourage clumps of native trees and shrubs already grown and thrifty, but where such do not exist the little time and outlay required for setting out and caring for these bird reserves will be richly repaid by the results.

(3) By carefully protecting the birds already occupying the premises. Present sentiment for the preservation of insectivorous birds is already strong in most parts of this country, and the chief need of protective laws is to insure the safety of our birds from foreign immigrants who, having been accustomed at home to kill for food any and all kinds of birds, large and small, young and old, naturally assume the same privileges in their adopted home. In some parts of the country, moreover, such birds as robins, bluebirds, nighthawks, killdeers, flickers, and other valuable species are slaughtered for food in vast numbers by our own citizens, either ignorant or careless of the fact that the country can ill afford to lose the services of these insectivorous species. The quail and prairie chicken are favorite and legitimate objects of pursuit by sportsmen, but they have been so ruthlessly pursued that they are now generally scarce and in many localities practically extinct. As the bobwhite is a most efficient weed destroyer, to say nothing of its being an active insect hunter, the farmer is called on to decide whether this bird is not too valuable on his farm to be shot for food or sport.

(4) By supplying water for birds. Though at first thought it may seem a small matter, a supply of water for drinking and bathing purposes is of great importance to birds. Running water is, of course, preferable, but shallow vessels distributed over the premises at short intervals in which a supply of water can be constantly renewed will be found to attract great numbers of birds and induce them to make their homes there.

WOODPECKERS.

From an economic standpoint our native woodpeckers may be divided into two classes. The first comprises the bulk of the family and includes upward of 50 species. All of these render extremely valuable service to the farmer, the horticulturist, and the forester. Specially equipped by Nature for digging into wood, they supplement the service of other species and destroy vast numbers of insects inaccessible to other birds. .

The second class comprises four species whose range collectively extends across the United States from ocean to ocean. These are

properly known as sapsuckers, for the reason that they excavate holes in the bark of trees for the purpose of obtaining their favorite food, which is the inner bark and the sap that exudes from the wounds. The injury thus inflicted on old trees is usually not so great as to affect their vitality seriously, but sapsuckers often cause the death of young trees. Moreover, after many years the timber from trees attacked by them reveals stains and defects which often materially lessen the value of the finished product. It is estimated that the damage to timber caused by these birds in the United States amounts to more than a million dollars annually. During the year bulletins were issued on both groups of woodpeckers, based on stomach examinations of many individuals and on extended field observations. The main purpose of these publications is to acquaint farmers and others with the part the several kinds of woodpeckers play, so as to enable them to distinguish friends from foes. Methods of protecting trees attacked by sapsuckers are given.

BIRDS OF ARKANSAS.

During the year an assistant of the bureau studied the birds of Arkansas and made careful observations of their habits. With the data thus obtained as a basis, a list of the birds of the State has been issued, no adequate list having previously been printed. In this list are recorded all the data resulting from the field work of the survey and all the information that could be gathered from other sources, with notes on the habits of the birds, especially in regard to their economic relations. We thus have for the first time an excellent idea of the avifauna of this important agricultural State.

FOOD OF WILD WATERFOWL.

The marked decrease in the number of our wild fowl in the last decade has attracted attention in every part of the country and caused much concern not only to sportsmen but to State authorities interested in the conservation of our natural resources. It is evident that increasingly stringent laws shortening the open season, prohibiting spring shooting, and decreasing the bag limit will materially aid in the preservation of the fast diminishing numbers of our waterfowl. The above measures may well be accompanied by action of the several States in setting apart suitable lakes and ponds for bird refuges where migrating waterfowl may safely resort and when so inclined may breed. Another important measure is the planting in suitable waters of native plants adapted to the varying taste of the more important kinds of ducks and geese. During the year investigations of the food of ducks and geese were continued, and field work in connection with these important investigations was done in Arkansas, Tennessee, Texas, Louisiana, and Florida. Many of the important winter feeding grounds of ducks and geese in these States were visited, and the feeding habits of the various species were carefully studied. A preliminary circular on the food of waterfowl was issued with a view of awakening interest in the subject and of supplying practical information in response to the many letters of inquiry from various parts of the United States.

EPIDEMIC AMONG WILD DUCKS AT GREAT SALT LAKE.

Following a long dry season, which favored the rearing of a large number of wild ducks, but materially reduced the area of the feeding ponds, resulting in great overcrowding, a severe epidemic broke out about August 1, 1910, among the wild ducks about Great Salt Lake, Utah. Dead ducks could be counted by thousands along the shores and the disease raged unabated until late fall. Shooting clubs found it necessary to declare a closed season. Some of the dead ducks were forwarded to the Biological Survey and were turned over for examination to the Bureau of Animal Industry, by the experts of which the disease was diagnosed as intestinal coccidiosis.

Various plans of relieving the situation were tried: The irrigation ditches were closed, thus providing the sloughs and ponds with fresh water, and lime was sprinkled on the mud flats and duck trails. Great improvement followed this treatment, and experiments proved that ducks provided with abundant fresh water and clean food began to recover immediately. These methods promised success, but later it was proposed that the marshes be drained and exposed to the sun's rays a course which can not be recommended. That coccidia are not always killed by exposure to the sun is shown by their survival on the sites of old chicken yards. An added disadvantage of the plan is that draining and drying the marshes would have a bad effect on the natural duck foods and upon the birds themselves.

ALFALFA WEEVIL.

The recently imported alfalfa weevil threatens to add a very injurious insect pest to the many existing in the United States. Already seriously destructive in Utah, should the insect continue to spread it is likely to endanger the alfalfa industry throughout the Western States. The Biological Survey is cooperating with the Bureau of Entomology in investigations to devise means of checking the spread of the weevil. Preliminary work has already shown that a number of birds feed on the insect, and it is hoped to spread this information among the farmers and so secure their aid in furthering measures for the protection and increase in numbers of these particular species.

GROUND SQUIRRELS.

During the year field investigations and experiments were continued to discover better methods of destroying ground squirrels in the National Forests and elsewhere. In order to test the efficacy and cheapness of the strychnine-starch solution recommended in Circular No. 36, several demonstrations on a rather extensive scale were undertaken in California. The Kern County Land Co., of California, under the supervision of the Biological Survey, successfully treated 29,000 acres of alfalfa with poisoned grain for the purpose of exterminating ground squirrels over the area. At the Jesus Maria Rancho an assistant of the Biological Survey supervised the destruction of ground squirrels over about 25 square miles of range lands and practically exterminated them at a cost of about 4 cents an acre. In winter, experiments were carried on in the San Joaquin

Valley for the purpose of finding a bait for use in the winter or wet season as effective as the strychnine-barley bait in the dry season— so far, however, without success.

RODENTS IN RELATION TO REFORESTATION.

Cooperative work with the Forest Service was continued during the year to devise methods of preventing the destruction of seeds in reforesting enterprises in the National Forests. Experiments were conducted in the Black Hills Forest of South Dakota, the Pike Forest of Colorado, the Pecos Forest of New Mexico, and the Coconino Forest of Arizona. The only practicable means to insure the safety of newly grown or planted seed was found to be the destruction of the small rodents infesting the tract. This is best done by means of poisoned bait prior to the seeding. Whether the same methods and same bait will prove as efficacious elsewhere as in the Rocky Mountain regions remains to be determined, but it is believed that by the methods set forth in Circular No. 78, "Seed Eating Mammals in Relation to Forestry," the loss during reforesting operations in the Rocky Mountain region can be reduced to a minimum.

PRAIRIE DOGS. :

Prairie dogs still continue to be a pest in certain States, and in regions where new land is being brought under cultivation sometimes render successful crop raising by farmers of small means impossible. They also indirectly cause great loss to stockmen by eating forage plants and thus limiting the number of cattle that can be carried on a given range. In cooperation with the Forest Service it is hoped eventually to exterminate these pests within the National Forests. Until, however, the several States take concerted action looking to the destruction of all prairie dogs within their boundaries, there can be no permanent diminution of these pests and no final abatement of the damage they cause. The preparation and sale to the farmers by the State experiment stations, or other authorized agencies, of poisoned bait at cost would greatly stimulate the work of ridding agricultural and pasture lands of the rodents. During the year demonstration work was carried on in Montana, Wyoming, California, New Mexico, Arizona, and Kansas with the starch-barley preparation, which appeared to be exceedingly effective with these animals even where there is green forage. Notwithstanding the fact that the animals are partial to oats, in some cases barley has been found to be a more effective vehicle for poison, as the hull which carries the poison can not be so easily removed.

MOLES.

That moles do much damage to lawns has long been known, and in addition farmers often charge them with the destruction of potatoes and other crops; but until recently the mole has not usually been classed among noxious animals, since it has been assumed that its food consists almost exclusively of insects and earthworms. Recent investigations show, however, that while the animal does much good

by destroying insects it also attacks crops to some extent, especially seed corn, although much of the damage attributed to this animal is due to field mice, which habitually use the runways of the moles. Efforts are being made to secure the stomachs of môles from different agricultural sections of the country with the view of increasing our knowledge of the food habits of this little mammal, and a bulletin will be issued defining its economic status and explaining methods of destroying it when necessary by traps and poisons.

FUR-BEARING ANIMALS.

The present high price of furs is due less to passing fashion than to the actual and growing scarcity of fur-bearing animals. As wearing apparel and for personal adornment furs occupy a place of their own, and there seems to be no acceptable substitute for them. For years the demand for furs has been greater than the supply, and, chiefly as a result of the encroachments of civilization on the breeding range of the animals and the unceasing activity of trappers, the number of fur bearers has been greatly reduced. If in the future furs are to be worn by any but the rich, it would seem that recourse must be had to fur farming on a large scale. The fur bearers best adapted for artificial breeding appear to be foxes, minks, and martens. Attempts to raise these animals, especially the first two named, are being made by private parties in various parts of this country and Canada. So far none of these enterprises appear to have passed the experimental stage, although a number of breeders of the silver fox claim to have made the business remunerative. It is believed that under suitable climatic conditions and with a fair understanding of the nature and methods of the business, the rearing of foxes and minks, and perhaps also martens, can be made a permanent and profitable occupation. The experiments now under way are being watched with great care, and all possible information is being obtained from breeders as to the treatment and feeding of the animals, with a view of ultimately issuing bulletins on the subject to supplement the two already published on fox farming and the muskrat industry.

COOPERATIVE WORK IN RELATION TO SPOTTED FEVER.

In cooperation with the Bureau of Entomology and the State experiment station of Montana much work was done by the Biological Survey during the year in Bitterroot Valley, Mont., to determine which of our native mammals act as hosts of the fever tick and thus aid in spreading spotted fever. In one or another stage of development fever ticks were found on no fewer than 18 of the wild mammals of the district. Some of these, like the larger game animals, are so scarce and inhabit places so remote from the habitations of men that they probably have little to do with the spread of the disease. Others, however, particularly ground squirrels, woodchucks, pine squirrels, and chipmunks, are very numerous in both cultivated and waste places contiguous to farms and villages, and any plan for permanently freeing the valley from fever ticks necessarily involves the extermination or the material reduction in numbers of these mammals. Thorough investigations are now being made by one of