The Bird Study Book Part 3

[Ill.u.s.tration: Young robins quarreling at their bath. Photographed in the yard of Mrs. Granville Pike, North Yakima, Washington]

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There is a theory held by many naturalists that the migrating instinct dates back to the glacial period. According to this theory North America was inhabited originally by non-migrating birds. Then the great Arctic ice-cap began to move southward and the birds were forced to flee before it or starve. Now and then during the subsequent period the ice receded and the birds returned, only to be driven again before the next onrush of the Ice King. Thus during these centuries of alternate advance and retreat of the continental glacier, the birds acquired a habit, which later became an instinct, of retreating southward upon the approach of cold weather and coming back again when the ice and snow showed indications of pa.s.sing away.

_The Gathering Flocks._--To the bird student there is keen delight in watching for the first spring arrivals and noting their departure with the dying year. It is usually in August that we first observe an unwonted restlessness on the part of our birds which tells us that they have begun to hear the call of the {66} South. The Blackbirds a.s.semble in flocks and drift aimlessly about the fields. Every evening for weeks they will collect a chattering mult.i.tude in the trees of some lawn, or in those skirting a village street, and there at times cause great annoyance to their human neighbours.

Across the Hudson River from New York, in the Hackensack marshes, behind the Palisades, clouds of Swallows collect in the late summer evenings, and for many days one may see them from the car windows as they glide through the upper air or swarm to roost among the rushes.

These Swallows and the Blackbirds are getting together before starting on their fall migration.

In Greensboro, North Carolina, there is a small grove of trees cl.u.s.tered about the courthouse which is a very busy place during the nights of summer. Here, before the first of July, Purple Martins begin to collect of an evening. In companies of hundreds and thousands, they whirl about over the tops of the houses, alight in the trees, and then almost {67} immediately dash upward and away again. Not till dark do they finally settle to roost. Until late at night a great chorus of voices may be heard among the branches. The mult.i.tude increases daily for six or eight weeks, additions, in the form of new family groups, constantly augmenting their numbers. Some time in September the migration call reaches the Martins, and, yielding to its spell, they at once depart toward their winter home in tropical South America.

_The Usual Movement._--Many of our smaller birds, such as Warblers and Vireos, do not possess a strong flocking instinct, but, nevertheless, they may be seen a.s.sociated in numbers during the season of the northern and southern movements. Such birds migrate chiefly at night and have been observed through telescopes at high alt.i.tudes. Such observations are made by pointing the telescope at the disk of the full moon on clear nights. On cloudy or foggy nights the birds fly lower, as may be known by the clearer sounds of their calls as they pa.s.s over; at times one may even hear the flutter of their wings. There is a {68} good reason for their travelling at this time, as they need the daylight for gathering food.

There appear to be certain popular pathways of migration along which many, though by no means all, of the aerial voyageurs wing their way.

As to the distribution of these avian highways, we know at least that the coastlines of the continents are favourite routes. Longfellow, in the valley of the Charles, lived beneath one of these arteries of migration, and on still autumn nights often listened to the voices of the migrating hosts, "falling dreamily through the sky."

A small number of the species migrate by day; among these are the Hawks, Swallows, Ducks, and Geese. The last two groups also travel by night. The rate at which they proceed on their journey is not as great as was formerly supposed. From twenty to thirty miles an hour is the speed generally taken, and perhaps fifty miles an hour is the greatest rapidity attained. Flights are usually not long sustained, a hundred and fifty miles a day being above the {69} average. Individuals will at times pause and remain for a few days in a favourable locality before proceeding farther. When large bodies of water are encountered longer flights are of course necessary, for land birds cannot rest on the water as their feathers would soon become water-soaked and drowning would result. Mult.i.tudes of small birds, including even the little Ruby-throated Hummingbird, annually cross the Gulf of Mexico at a single flight. This necessitates a continuous journey of from five hundred to seven hundred miles. Some North American birds migrate southward only a few hundred miles to pa.s.s the winter, while many others go from Canada and the United States to Mexico, Central and South America.

The ponds and sloughs of all that vast country lying between the Great Lakes and Hudson Bay on the east and the mountains of the Far West, const.i.tute the princ.i.p.al nursery of North American waterfowl, whence, in autumn, come the flocks of Ducks and Geese that in winter darken the Southern {70} sounds and lakes. One stream moves down the Pacific Coast, another follows the Mississippi Valley to the marshes of Louisiana and Texas, while a third pa.s.ses diagonally across the country in a southeasterly direction until it reaches the Maryland and Virginia coastline. Thence the birds disperse along the coastal country from Maine to Florida.

[Ill.u.s.tration: Migration Routes of Some North American Birds]

_The Travelling Sh.o.r.e Birds._--Turnstones, Sanderlings, Curlews, and other denizens of the beaches and salt marshes migrate in great numbers along our Atlantic Coast. Some of them winter in the United States, and others pa.s.s on to the West Indies and southward. The extent of the annual journeys undertaken by some of these birds is indeed marvellous.

Admiral Peary has told me that he found sh.o.r.e birds on the most northern land, where it slopes down into the Arctic Sea, less than five hundred miles from the North Pole; and these same birds pa.s.s the winter seven thousand miles south of their summer home. One of these wonderful migrants is the Golden Plover. In autumn the birds leave {72} eastern North America at Nova Scotia, striking out boldly across the Atlantic Ocean, and they may not again sight land until they reach the West Indies or the northern coast of South America. Travelling, as they do, in a straight line, they ordinarily pa.s.s eastward of the Bermuda Islands. Upon reaching South America, after a flight of two thousand four hundred miles across the sea, they move on down to Argentina and northern Patagonia. In spring they return by an entirely different route. Pa.s.sing up through western South America, and crossing the Gulf of Mexico, these marvellous travellers follow up the Mississippi Valley to their breeding grounds on the sh.o.r.es of the Arctic Ocean. Their main lines of spring and fall migration are separated by as much as two thousand miles. During the course of the year the Golden Plover takes a flight of sixteen thousand miles.

_The World's Migrating Champion._--The bird which makes the longest flight, according to the late Wells W. Cooke, America's greatest authority on bird migration, is the Arctic Tern. Professor Cooke, to {73} whom we owe so much of our knowledge of the subject, says of this bird:

"It deserves its t.i.tle of 'arctic' for it nests as far North as land has been discovered; that is, as far North as the bird can find anything stable on which to construct its nest. Indeed, so arctic are the conditions under which it breeds that the first nest found by man in this region, only seven and one-half degrees from the pole, contained a downy chick surrounded by a wall of newly fallen snow that had been scooped out of the nest by the parent. When the young are full grown the entire family leaves the Arctic, and several months later they are found skirting the edge of the Antarctic continent.

"What their track is over that eleven thousand miles of intervening s.p.a.ce no one knows. A few scattered individuals have been noted along the United States coast south to Long Island, but the great flocks of thousands and thousands of these Terns which range from pole to pole have never been noted by ornithologists competent to indicate their {74} preferred route and their time schedule. The Arctic Terns arrive in the Far North about June fifteenth and leave about August twenty-fifth, thus staying fourteen weeks at the nesting site. They probably spend a few weeks longer in the winter than in the summer home, and this would leave them scarcely twenty weeks for the round trip of twenty-two thousand miles. Not less than one hundred and fifty miles in a straight line must be their daily task, and this is undoubtedly multiplied several times by their zigzag twistings and turnings in pursuit of food.

"The Arctic Tern has more hours of daylight and sunlight than any other animal on the globe. At the most northern nesting site the midnight sun has already appeared before the birds' arrival, and it never sets during their entire stay at the breeding grounds. During two months of their sojourn in the Antarctic the birds do not see a sunset, and for the rest of the time the sun dips only a little way below the horizon and broad daylight is continuous. The birds, therefore, have twenty-four hours of daylight for at least {75} eight months in the year, and during the other four months have considerably more daylight than darkness."

_Perils of Migration._--The periods of migration are fraught with numerous perils for the travelling hosts. Attracted and blinded by the torches of lighthouses, mult.i.tudes of birds are annually killed by striking against lighthouse towers in thick, foggy weather. The keeper of the Cape Hatteras light once showed me a chipped place in the lens which he said had been made by the bill of a great white Gannet which one thick night crashed through the outer protecting gla.s.s of the lighthouse lamp. As many as seven hundred birds in one month have killed themselves by flying against the Bartholdi Statue of Liberty in New York Harbour. As its torch is no longer lighted the death-rate here has been greatly reduced, although some birds are still killed by flying against the statue. Many were formerly killed by striking the Washington Monument, the record for one night being one hundred and fifty dead birds.

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Locomotive engineers have stated that in foggy weather birds often hurl themselves against the headlight and frequently their bodies are later picked up from the engine platform beneath. Birds seem rarely to lose their sense of direction, and they pursue their way for hundreds of miles across the trackless ocean. Terns, Gulls, and Murres are known to go many miles in quest of food for their young and return through dense fogs with unerring directness to their nests.

[Ill.u.s.tration: Lighthouses Cause the Death of Many Birds]

During the spring it is not uncommon for strange waterfowl to be found helpless in the streets or fields of a region in which they are ordinarily unknown. These birds have become exhausted during the storm of the night before, or have been injured by striking telephone or telegraph wires, an accident which often happens. Once I picked up a Loon after a stormy night. Apparently it had recovered its strength after a few hours' rest, but, as this bird can rise on the wing only from a body of water, over the surface of which it can paddle and flap for many rods, and as {78} there was no pond or lake in all the neighbouring country, the Loon's fate was evident from the first.

Birds are often swept to sea by storm winds from off sh.o.r.e. Vainly they beat against the gale or fly on quivering wings before its blast, until the hungry waves swallow their weary bodies. One morning in northern Lake Michigan I found a Connecticut Warbler lying dead on the deck beneath my stateroom window after a stormy night of wind and rain.

Overtaken many miles from sh.o.r.e, this little waif had been able to reach the steamer on the deck of which it had fallen exhausted and died. What of its companions of the night before?

On May 3, 1915, I was on a ship two hundred miles off Brunswick, Georgia. That day the following birds came aboard, all in an exhausted condition: Brown Creeper, Spotted Sandpiper, Green Heron, and Yellow-billed Cuckoo. We also encountered three flocks of Bobolinks, which for some distance flew beside the ship. They appeared to be lost, for they all left us finally, flying straight ahead of the ship, {79} which was bound South, yet birds were supposed to be going North at this season. I wonder if in their bewilderment they mistook the ship for some immense bird pointing the way to land and safety!

[Ill.u.s.tration: Tired Migrating Birds Often Alight on Ships]

_Keeping Migration Records._--More than thirty {80} years ago the United States Government put into operation a plan for collecting and tabulating information concerning the dates on which migratory birds reach various points in their journeys. More than two thousand different observers located in various parts of the country have contributed to these records, many of the observers reporting annually through a long series of years. As a result of this carefully gathered material, with the addition of many data collected from other sources, there is now on file in Washington an immense volume of valuable information, much of which, in condensed printed form, is obtainable by the public. This work was in charge of Professor Wells W. Cooke, Biologist, in the Biological Survey of the United States Department of Agriculture until his lamented death in the spring of 1916. Who will take charge of it hereafter is not yet determined; but students may obtain from the director of the Survey migration schedule blanks upon application, and bulletins describing the emigration habits of various North American birds. {81} Watching for the annual appearance of the first individual of each species is most fascinating occupation.

[Ill.u.s.tration: Feeding station for birds on the grounds of R. G.

Decker, Rhinebeck, New York. The gla.s.s sides prevent the seeds from being blown off the tray a foot or more below the roof.]

Note.--Government bulletins on the migration of various North American birds may be obtained free, or at slight cost, by addressing H. W.

Henshaw, Chief Biological Survey, Department of Agriculture, Washington, D. C.

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CHAPTER V

THE BIRDS IN WINTER

With the approach of winter the country loses its charm for many people.

The blossoms and verdure, so common yet so beloved by all, have departed, and only the brown expanses of dead gra.s.s and weeds relieve the blackness of the forest trees. Even ardent nature lovers have been known to forsake their walks at this season when the songs of the birds have ceased and the forest boughs give forth only sobs and shrieks as they sway to the strength of the north winds.

_A Good Time for Field Walks._--Nevertheless winter is a good time for the bird student to go afield. If the wild life is less abundant, so is the human life, and you have the country almost to yourself. If you but say in your heart, "I will go and see what may be {83} found," you will later rejoice, for with the falling of the leaves many of Nature's secrets, which she has jealously guarded through the summer months, stand revealed. Among the naked branches of the briars you may find the Catbird's nest which defied all search last June. It will be a comfort to learn that the bird really did have a nest just about the place you thought it was located. Many other pleasing surprises await you in the winter woods.

_The Downy's Winter Quarters._--One late autumn day I stopped to watch a Junco feeding among some weed stalks near a hillside trail. After remaining motionless for a minute or two I became conscious of a light m.u.f.fled tapping somewhere near by. It did not take long to locate the sound. On the underside of a slanting decayed limb, twenty feet above, was a new, well-rounded hole perhaps an inch in diameter. Even as I looked the occupant came to the entrance and threw out a billful of small chips. When these fell, I saw that the dead leaves on the earth beneath had been well sprinkled by previous ejections {84} of the same nature. I had discovered a Downy Woodp.e.c.k.e.r at work on his winter bedroom, and later I had reason to believe that he made this his nightly retreat during the cold months that followed.

Chancing to pa.s.s this way one dark cloudy morning, it occurred to me to look and see if he had yet left his bed. Striking the limb near the hole I was rewarded by seeing a little black-and-white head poked out inquiringly. Fearing he might be resentful if such treatment were repeated, I never afterward disturbed my little neighbour while he was taking his morning nap. But I had learned this much, that one Downy at least sometimes liked to be abed on cold mornings. Perhaps he knew that there was no early worm about at this season.

_Birds and the Night._--It may be that others of our winter birds also make excavations for sleeping quarters; the Chickadee and Nuthatch very probably do so, although I have never found them thus engaged. It is well known that many small birds creep into holes to pa.s.s the night. Old nesting {85} places of Woodp.e.c.k.e.rs are thus again rendered useful, and many of the natural cavities of trees contain, during the hours of darkness, the little warm, pulsating bodies of birds.

Quails invariably roost on the ground regardless of the time of year, or the prevailing weather conditions. An entire covey numbering sometimes twelve or fifteen will settle for the night in a compact circular group with heads pointed outward. When a heavy snow falls they are completely buried, and then if a hard crust forms before morning their roosting place becomes their tomb. Grouse now and then are trapped in the same way, but their superior strength enables them to break through and escape. In fact, these larger birds often deliberately go to roost beneath the snow, breaking through the crust by a swift plunging dive from the air. Bearing these facts in mind it is easy to understand why Quails often become scarce in a country where Grouse abound.

Small birds pa.s.s the winter nights in evergreens, thick-growing vines, under the eaves of verandas, or {86} on the rafters of bridges. Many creep into cracks of outhouses. I have found them at night in caves, barns, and once in a covered wagon. Almost any available shelter may have its bird tenant on cold nights, who if undisturbed will often return again and again to the refuge it has once found safe and comfortable.

Birds that pa.s.s the winter in the Northern States are subjected to many hardships. In fact, the fatalities in the bird world in winter are so great, and the population so constantly reduced by one form of tragedy or another, that it is only the stronger and more fortunate individuals of a species that survive to enjoy the summer.

_The Food Question in Winter._--Where to secure the food is the big question which confronts every bird when it opens its eyes on the first snowy morning of winter. Not only has the whole aspect of the country been changed, but the old sources of food have pa.s.sed away. Not a caterpillar is to be found on the dead leaves, and not a winged insect is left to come flying {87} by; hence other food must be looked for in new directions. Emboldened by hunger, the Starlings alight at the kitchen door, and the Juncos, Sparrows, Downy Woodp.e.c.k.e.rs, and Nuthatches come to feed on the window-sill. Jays and Meadowlarks haunt the manure piles or haystacks in search of fragments of grain. Purple Finches flock to the wahoo elm trees to feed on the buds, and Crossbills attack the pine cones. Even the wary Ruffed Grouse will leave the shelter of the barren woods, and the farmer finds her in the morning sitting among the branches of his apple tree, relieving the twigs of their buds. In every field a mult.i.tude of weed stalks and stout gra.s.s stems are holding their heads above the snow tightly clasping their store of seeds until members of the Sparrow family shall thrash them out against the frozen crust beneath.

Among those which are forced to become largely vegetarian in winter is the Bluebird. In summer he is pa.s.sionately fond of gra.s.shoppers, cutworms, and _Arctia_ caterpillars, but now he wanders sadly over {88} the country of his winter range in quest of the few berries to be found in the swamps and along the hedgerows. The Crow is another bird often met in winter walks, for he, too, in many cases spurns the popular movement southward in the fall, and severe indeed must be the weather before he forsakes his former haunts. You will find him feeding along the banks of streams or in the open spots in the fields, or {89} again in the woods pecking rotten stumps or fallen limbs in search of dormant beetles.

[Ill.u.s.tration: Grouse "Budding" in an Apple Tree]

Fifty-five species of Warblers inhabit North America. These birds are insectivorous in their feeding habits, which of course also means that they are migratory. A partial exception to the rule is found in the common Myrtle Warbler. Although in winter these birds range south to Panama, many remain as far north as New Jersey, Kansas, and the Ohio Valley. This does not mean that insects are found in these regions in sufficient numbers to supply the larder of the Myrtle Warblers, but it does mean that they find acceptable subst.i.tutes for their usual food.

Oddly enough, what they depend on is not animal matter in any form, but consists of berries which contain some of the essential food properties of fatty meats. One of the most popular with them is the common bayberry.

Among the sand dunes of the extensive "Banks" along the North Carolina coast there grows in great profusion a small bushy tree known as the yaupon. {90} The young leaves of this when dried and steeped make a very acceptable drink, and during the hungry days of the Civil War when the Federal blockade became effective the people of the region used this as a subst.i.tute for tea and coffee. The yaupon produces in great abundance a berry that is so highly esteemed by the Myrtle Warblers that they pa.s.s the winter in these regions in numbers almost incredible.

_When the Food Supply Fails._--It is hard to realize the extent of the havoc wrought among birds by cold, snowy weather. Early in the year 1895 a long, severe cold spell, accompanied by snow and sleet, almost exterminated the Bluebird in the eastern United States. The bodies of no less than twenty-four of these birds were found in the cavity of one tree. It looked as if they had crowded together with the hope of keeping warm. It was not the cold alone which had destroyed the birds: a famine had preceded the cold snap, and the birds, weakened by hunger, were ill prepared to withstand its rigours.

One winter some years ago a prolonged freezing {91} wave swept over our South Atlantic States, and played havoc with the Woodc.o.c.k in South Carolina. This is what happened: the swamps in the upper reaches of the Pee Dee, the Black, and Waccamaw rivers were frozen solid, and the Woodc.o.c.k, that in winter abound in this region, were thus driven to the softer grounds farther downstream. The cold continued and the frozen area followed the birds. The Woodc.o.c.k, unable to drive their long bills into the once-responsive mud, were forced to continue their flight toward the coast in search of open ground where worms could be found. When at length they reached Winyaw Bay, where these rivers converge, they were at the point of exhaustion. Thousands of the emaciated birds swarmed in the streets and gardens of Georgetown. They were too weak to fly, and negroes killed them with sticks and offered baskets of these wasted bodies, now worthless as food, for a few cents a dozen. Several shipments were made to Northern cities by local market men, who hoped to realize something by their industry.