404 BULLETIN 203, UNITED STATES NATIONAL MUSEUM 



exhausted condition. C. J. Maynard (1896), who landed April 27, 

 1884, on a small key in the Bahamas, found great numbers of black- 

 polls, some of which he found dead apparently due to exhaustion. 

 W. E. D. Scott (1890) in writing of the spring migration at Tarpon 

 Springs in 1888 states : 



It is so rare that one finds any birds dying or dead from otlier than accidental 

 causes, generally connected in some way with innovations caused by the settle- 

 ment of a country, as telegraph wires, light-houses, and the like, that it seems 

 worth while to give the following details of an epidemic. It was apparently 

 conhned, as far as I am aware, to the representatives of this species alone, and 

 only to those individuals which visited the Anclote Keys and Hog Island. These 

 keys are four in number, and are four miles from the main land, in the Gulf, 

 and extend in a north and south line for about twenty-five miles. I found in late 

 April and early May many D[cnd7-oica] striata dead, and others apparently ill 

 unto death on these islands. ♦ * * i picked up dead on April 29, 1888, in a 

 short walk on South Anclote Key, upwards of twenty-five. 



Scott presents no evidence of disease or cause of the so-called epidemic, 

 and I am inclined to believe these birds were members of a late migra- 

 tory wave that had met with adverse conditions and died of 

 exhaustion. 



The habit of migrating at night is indirectly a cause of great mor- 

 tality when waves of these birds encounter lighthouses and lighted 

 tow^ers. Often very serious conditions prevail during cloudy or foggy 

 nights when the birds, losing their bearings and attracted by the 

 bright light, descend from their high-level flight and are dashed to 

 death on striking some part of an illuminated tower. William 

 Dutcher (1888) writes that of the 595 birds killed by striking the Fire 

 Island Light on Long Island on September 23, 1887, no less than 356 

 were blackpoll warblers. 



W. E. Saunders (1930) has reported great destruction at the Long 

 Point Lighthouse, Ontario, on Lake Erie, during September 1929. On 

 September 7 there w^ere 31, on September 9, 6 and on September 

 24-29, 199 blackpolls that met their death by flying into the light. 

 Similar conditions prevail along the Maine coast where during cloudy 

 and stormy nights many warblers, including a large percentage of 

 blackpolls, are killed. 



High towers such as the Washington Monument also exact a heavy 

 toll on night-flying birds. Kobert Overing (1938) reports that in the 

 course of an hour and a half, 10 :30 p. m. to midnight of September 12, 

 1937, 576 individual birds, chiefly warblers and including the black- 

 poll, were dashed to their death. At this time the humidity ranged 

 from 65 to 75 percent, and a mist enveloped the top of the shaft. 

 These and numerous other instances indicate that lighthouses and 

 towers are a great menace to a night-migrating bird sucli as the black- 

 poll. Probably m^ore individuals meet violent death in this manner 

 than by any other way. 



