Part 3

HELPING OUR BIRD FRIENDS

We may encourage birds to live about us, if we bear in mind their needs. In winter we may feed the Chickadees, Cardinals, Downy Woodpeckers, and other birds which live in our neighborhood. We may tack pieces of suet on a sheltered branch and scatter grain and grit on “feeding counters.” When snow is on the ground the birds have considerable difficulty in getting enough food, and our assistance will sometimes keep them from starvation. Feeding-shelters may be very simple, or they may be elaborate, but they should be placed and built so as to serve the needs of the birds best. A feeding-shelf built at a window furnishes a very attractive and useful device.

Before spring is upon us we should erect nesting-boxes for the Purple Martins, Bluebirds, and House Wrens we wish to attract. Those who are interested in securing specifications for these boxes should write to the Game Commission at Harrisburg for their bulletin, “A Year’s Program for Bird Protection.”

In spring we should think of the trees or shrubs which will attract birds. A fruit-laden mulberry tree always attracts birds in midsummer. Thick bushes placed in clumps will almost surely lure nesting Catbirds or Chipping Sparrows; a trumpet vine will mean Hummingbirds!

In midsummer the birds’ bath must be arranged. Such a bath may be very simple. But it must not be deep, and the edges should slope into the deeper water gradually. Remember that the water should be changed frequently unless a running stream is provided.

House cats and birds do not thrive together as a rule. If you wish to make conditions as nearly ideal as possible for your bird friends, you had better not keep a cat, for these animals are, by nature, crafty and bloodthirsty, and they will catch birds for “sport,” even though they are well fed.

If you carefully watch the birds, you will become aware of their needs. You may find it necessary to shoot Starlings occasionally if they persist in ousting Flickers from their nests. You may have to plant sunflowers to attract Goldfinches; you may find it desirable to allow part of your property to grow up into weeds and bushes so that it may furnish a home for some unusual bird neighbor. At my home at Bethany, West Virginia, we have permitted raspberry vines to grow on a hillside back of the house, and here Indigo Buntings nest, within a few rods of the open windows!

LIFE-ZONES IN PENNSYLVANIA

The term Life-Zone is used by scientists in referring to a region where environmental conditions so react upon each other as to form a suitable home for certain plant and animal forms. A Life-Zone naturally has no hard and fast boundaries as does a geographical zone; its boundaries are determined by temperature, rainfall, soil, altitude, drainage, and innumerable other factors, which so create a certain average whole as to attract certain species of plants, birds, mammals, and so forth, which in turn themselves become part of the environment, and are responsible for the presence of certain forms. These Life-Zones are, then, associations which naturally develop in sections where similar conditions exist. In Pennsylvania there are three or four of these associations. One, noticeable in the southern and southwestern counties, has been called the Carolinian Life-Zone. Here such birds as the Carolina Wren, Cardinal, Tufted Tit, and Red-bellied Woodpecker live. In much of Pennsylvania the Alleghenian Life-Zone occurs, where the Least Flycatcher, Wilson’s Thrush, Swamp Sparrow, and Rose-breasted Grosbeak are to be found in summer. Higher in the mountains is the Canadian Life-Zone; here the Junco, Hermit Thrush, Red-breasted Nuthatch, Wilson’s Snipe, and Northern Water Thrush nest. As you read this book, you will notice that many birds are to be found in northern or mountainous counties; others in southern or less mountainous counties, and so forth. This is an indication of Life-Zone distribution.

BIRD-MIGRATION IN PENNSYLVANIA

Some of our winter birds spend the year round in one region. Certain of them, like the Song Sparrow and Crow, migrate to an extent, the nesting individuals moving southward during winter, their place being taken by other individuals of the same species from farther north. Some winter birds, such as the Junco, Golden-crowned Kinglet, Brown Creeper, and Tree Sparrow, visit us from the north and return to their Canadian nesting-ground with the arrival of spring. Most of our familiar summer birds spend the winter to the southward, many of them in South America. They come to us for a few months each year for the sole purpose of bringing forth their young. Many species of birds pass through Pennsylvania en route from their home in the south to their nesting-grounds in the north, and back again in the fall.

By far the greater number of species migrate to an extent. The phenomenon of bird-migration has caused many a student to wonder. How did such a tremendous annual movement originate? How do the birds endure their great flights across bodies of water?

The probability is that the migration of birds developed in past centuries as the food-supply in the tropics became insufficient for all the nesting birds which tried to bring forth their young there. Urged by the need for solitude and a good food-supply, certain birds pushed out from the ancestral range and established a new summer home. After the young were reared, instinct drew them back to the region which was familiar to them, and so great migration routes have developed. Today the tiny Ruby-throated Hummingbird rears his young in our woodlands, then returns to South America with the young birds. Our Yellow Warbler, Red-eyed Vireo, Purple Martin, Rose-breasted Grosbeak, Scarlet Tanager, and many others, all go to South America.

Food-conditions, no doubt, have something to do with migration movements. Birds are well clothed with feathers, to be sure, but many of them depend on an insect diet, such as would be difficult to secure during cold winters. Some of our birds actually do not migrate if a food-supply is available.

Most of the smaller birds migrate at night, following streams or mountain ranges. Swallows and hawks usually migrate by day, ducks and geese by both day and night. The Ohio, Delaware, and Susquehanna river valleys are important routes of migration. The shore of Lake Erie is a resting-ground for birds which have flown over this large body of water. In fall, at Presque Isle, the trees may be alive with birds which have just made the flight. The Atlantic Coast is an important route of migration for many waterbirds. Since Pennsylvania has no salt-water shore-line, we do not find some species which are to be found along the coast of New Jersey and Delaware.

Many birds which occur in abundance at Erie, in fall, rest there until they are able to take another flight; then they start southward for a feeding or resting-ground south of Pennsylvania, and therefore skip over most of the Commonwealth.

The distribution of birds and the constancy of their migration routes is a source of much wonder to all of us. Why should the two Palm Warblers, for instance, so invariably be found each year, one to the eastward, one to the westward of the mountains? Why should some birds be here in fall and not in spring? Why should others be so variable in numbers? If you keep careful notes upon the migratory birds, you may eventually help to solve some of these problems.

HORNED GREBE Colymbus auritus Linnæus

Other Names.—Dipper; Hell-Diver.

Description.—Neck long; no tail-feathers; toes flat and broad, feet at rear of body; sexes similar. Adult in spring: Large, puffy head, black, with stripe and silken plumes behind eye buffy; plumage of back blackish edged with gray; secondaries white; neck, breast, and sides chestnut; belly silvery white; eyes bright pink, the pupil encircled with a white ring. Immature birds and adults in winter: Grayish black above, silvery white beneath, grayish on the throat, with white cheek-patches which nearly meet on nape. Length: 13½ inches.

Range in Pennsylvania.—A migrant throughout the Commonwealth from March 20 to May 10 and from October 1 to November 30; occasional in winter when water is free of ice.

The white on the sides of the head and the white wing-patches distinguish this species in winter plumage from the Pied-billed Grebe; the gay spring plumage of the Horned Grebe is unmistakable. Look for this bright-eyed diver along the larger waterways. Its ability in swimming under water causes it to evade its enemies by disappearing beneath the surface rather than by flying. Grebes have the interesting habit of swallowing their own feathers as they moult, or as they pluck them out.

Holbœll’s Grebe (Colymbus holbœllii), a much larger bird, is very rare in Pennsylvania. In spring plumage it has a red-brown neck. It is about twice as large as either the Horned or Pied-billed Grebe and has a proportionately heavier and larger bill.

PIED-BILLED GREBE Podilymbus podiceps podiceps (Linnæus)

Other Names.—Dabchick; Hell-Diver; Dipper; Dipper-Duck (erroneous).

Description.—Sexes similar. Adults in summer: Glossy, dark brown above; throat black; neck, breast, and sides grayish, washed with brownish and indistinctly mottled with blackish; lower breast and belly glossy white; black band across bill. Immature birds and adults in winter: Similar, but without black on throat and bill. Length: 13½ inches.

Range in Pennsylvania.—Rare as a summer resident, chiefly because there are so few lakes and marshes suited to its nesting; fairly common as a migrant from April 1 to May 15 and from August 25 to October 30.

Nest.—Flat, composed of decaying vegetation, floating among water-weeds or anchored by plants which are attached to the bottom. Eggs: 4 to 7, dull white, usually so heavily stained as to be brownish in appearance.