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 whom we owe so much of our knowledge of the subject, says of this bird:
“It deserves its title 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 space 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 THE BIRD STUDY BOOK 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 thou-sand 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 al-ready 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, there-fore, have twenty-four hours of daylight for at least 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, multitudes 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 glass of the lighthouse lamp. As many as seven hundred birds in one month have killed them-selves 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.
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.
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 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 shore. 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 state-room window after a stormy night of wind and rain. Overtaken many miles from shore, 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, 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 !
Keeping Migration Records.More than thirty 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.
Watching for the annual appearance of the first individual of each species is most fascinating occupation.
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.