Page:Condor6(5).djvu/7

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Sept., 1904
THE CONDOR
117

cloudy nights when they can not possibly see the Florida shores, and safely reach their destination, provided no change occurs in the weather. But if meantime the wind changes or a storm arises to throw them out of their reckoning, they become bewildered, lose their way, and fly toward the light-house beacon. Unless killed by striking the lantern, they hover near or alight on the balcony, to continue their flight when morning breaks, or, the storm ceasing, a clear sky allows them once more to determine the proper course.

Birds flying over the Gulf of Mexico to Louisiana, even if they ascended to the height of five miles, would still be unable to see a third of the way across. Nevertheless this trip is successfully made twice each year by countless thousands of the warblers of the Mississippi Valley.

A favorite belief of many American ornithologists is that coast lines, mountain chains, and especially the courses of the larger rivers and their tributaries, form well-marked highways along which birds return to previous nesting sites. According to this theory a bird breeding in northern Indiana would in its fall migration pass down its own little rivulet to the nearest creek, along this to the Wabash River, thence to the Ohio, and finally reaching the Mississippi, would follow its course to the Gulf of Mexico; and would use the same route reversed for the return trip in the spring. The fact is that each county in the Central States contains nesting birds, the different species of which at the beginning of the fall migration scatter toward half the points of the compass. Indeed, it would be safe to say "all the points of the compass," as some young herons preface their regular journey south with a little pleasure trip to the unexplored North.

In the fall thousands of birds reared in Indiana, Illinois and northwestward visit South Carolina and Georgia, cutting directly across the valley of the Ohio and the main chain of the Allegheny Mountains. Palm warblers from New England and others from the Northern Mississippi Valley both pass in the fall through Georgia, but by courses approximately at right angles to each other; and the Connecticut warbler seeks variety by choosing different routes for the spring and fall, each course in part being at right angles to the other. The truth seems to be that birds pay little attention to natural physical highways, except when large bodies of water force them to deviate from the desired course. Probably there are many short zigzags from one favored feeding spot to another, but the general course between the summer and winter homes is as straight as the birds can find without missing the usual stopping places.

CASUALTIES DURING MIGRATION.

Migration is a season full of peril for myriads of winged travelers, especially for those that cross large bodies of water. Some of the shore birds, such as the plover and curlew, which take long ocean voyages can rest on the waves if overtaken by storms, but woe to the luckless warbler whose feathers once become water-soaked!—a grave in the ocean or a burial in the sand of the beach is the inevitable result. Nor are such accidents infrequent. A few years ago on Lake Michigan a storm during spring migration piled many birds along the shore. If such a mortality could occur on a lake less than 100 miles wide, how much greater might it not be during a flight across the Gulf of Mexico. Such a catastrophe was once witnessed from the deck of a vessel 30 miles off the mouth of the Mississippi River. Large numbers of migrating birds, mostly warblers, had accomplished nine-tenths of their long flight and were nearing land when they were caught by a "norther" with which most of them were unable to contend, and falling into the Gulf were drowned by hundreds. During migration, birds are