birds sometimes congregate in enormous numbers where grass or weed 

 seed is abundant. Almost every winter brings in reports of their 

 death by thousands somewhere in the Middle West. While migrating 

 northward at night they have encountered blinding storms of wet, 

 clinging snow, which have so bewildered them that they have flown 

 into various obstructions, or have sunk to the ground and perished of 

 exposure and exhaustion. In 1907 an experienced ornithologist esti- 

 mated that 750,000 longspurs were lying dead on the ice of 2 lakes in 

 Minnesota, each about i square mile in extent, and dead birds were 

 reported in greater or less abundance on this occasion over an area 

 of more than 1,500 square miles. The heaviest mortality occurred in 

 towns, where, bewildered by the darkness and the heavy falling snow, 

 some of the birds congregating in great numbers flew against various 

 obstacles and were killed or stunned, while many others fell to the 

 ground exhausted. Similar catastrophes have been reported from 

 eastern Colorado, Nebraska, and North Dakota. 



During the early part of June 1927, a hailstorm of exceptional sever- 

 ity in and around Denver, Colo., killed large numbers of robins, 

 meadow larks, sparrows, and others. The lawns of parks were strewn 

 with the bodies of these birds, and many lay dead in their nests where 

 they were covering their eggs or young when the storm broke. 



Aerial obstructions 



Lighthouses, lightships, tall bridges, piers, monuments, and other 

 aerial obstructions have been responsible for a tremendous destruction 

 of migratory birds. Beams of the lanterns at light stations have a 

 powerful attraction for nocturnal travelers of the air that may be 

 likened to the fascination for lights that also is shown by many insects, 

 particularly night-flying moths. The attraction is not so potent in 

 clear weather, but when the atmosphere is moisture laden, as in a heavy 

 fog, the rays have a dazzling effect that lures the birds to their death. 

 They may fly straight up the beam and dash themselves headlong 

 against the glass, or they may keep fluttering around the source of the 

 light until exhausted, and then drop to the rocks or waves below. The 

 fixed, white, stationary light located 180 feet above sea level at Ponce 

 de Leon Inlet (formerly Mosquito Inlet), Fla., has caused great de- 

 struction of bird life even though the lens is shielded by wire netting. 

 On one occasion an observer gathered up a bushel-basketful of warblers, 

 sparrows, and other small passerine birds that had struck during the 



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