Many are the disasters that befall them when they journey near the sea-coast. In Dr. Wells W. Cooke’s article entitled “Our Greatest Travelers” are the following statements: “It is not to be supposed that these long flights over the waters can occur without many casualties, and not the smallest of the perils arises from the beacons which man has erected along the coast to insure his own safety. ‘Last night I could have filled a mail-sack with the bodies of little warblers which killed themselves striking against my light,’ wrote the keeper of Fowey Rocks lighthouse, in southern Florida.
“Nor was this an unusual tragedy. Every spring the lights along the coast lure to destruction myriads of birds who are en route from their winter homes in the South to their summer nesting-places in the North. Every fall a still greater death-toll is exacted when the return journey is made. A red light or a rapidly flashing one repels the birds, but a steady white light piercing the fog proves irresistible.”[136]
Few people realize the great good done by warblers. Mr. Forbush says that in migration they seem to possess enormous appetites. A Hooded Warbler was found to catch on the average two insects a minute or one hundred and twenty an hour. At this rate the bird would kill at least nine hundred and sixty insects a day, in an eight hour working day!
Dr. Judd reported a Palm Warbler that ate from forty to sixty insects a minute. In the four hours he was under observation he must have eaten nine thousand, five hundred insects. Mr. Forbush says that he has seen warblers eating from masses of small insects at such a rate that it was impossible for him to count them.[137]
IDENTIFICATION OF WARBLERS
In order to identify warblers, most people need to group them in some way. The following grouping of my own has helped me to recognize and remember the more common species:
I The Ground Warblers
1 The Ovenbird
2 The Water Thrushes
3 The Worm-eating Warbler