NORTHERN AND MARYLAND YELLOWTHROATS 557 



scribed by Miss Florence M. Pease as follows : "On May 14, 1914, I saw a 

 Maryland yellow-throat fly very high, then spiral down and then fly off toward 

 the church, where it was still a good distance from the ground. I was not able to 

 estimate accurately how many feet the bird flew up, but I noted that when it 

 began to spiral down it was far, far above the church steeple. I had always 

 supposed that the flight-song of the Maryland yellow-throat was given from a 

 height of a few feet." 



Enemies. — The yellowthroat is subject to the usual enemies of birds 

 that nest near or on the groimd. I remember finding a nest of the 

 yellowthroat in a grassy area near a meandering meadow brook in 

 central Illinois where snakes were common. During a second visit 

 to the nest, when the young were 3 days old, I saw a large water moc- 

 casin disappearing into the vegetation as I approached. Two of 

 the young were missing and I presume, judging from the behavior of 

 the adults, they were victims of the unwelcome visitor. 



A. L. Rand (1943) cites a report from Lake Okeechobee, Fla., in 

 October 1942, where a 3-pound large-mouthed bass was found to 

 have a yellowthroat in its stomach. These fish often feed in shallow 

 water among the water-hyacinth where they could easily capture a 

 bird as they do various insects on or near the surface. Mr. Rand 

 mentions reports of other birds captured by black bass and since 

 yellowthroats are frequent visitors to such situations in quest of in- 

 sects, it may not be a rare incident. Turtles have been known to 

 caj^ture small birds and may also prove to be an enemy of the yellow- 

 throat. 



However, the number of yellowthroats that fall victims to natural 

 enemies are :^nsignificant when compared with the appalling losses 

 suffered by this species durhig the migration, especially when the 

 great migi-ation waves meet with severe storms and foggy weather. 

 D. E. Culver (1916) gives an account of a large number of birds that 

 were killed on May 21 and 22, 1915, by flying into public buildings and 

 the City Hall in Philadelphia. On May 21 theia was a heavy mist or 

 fog prior to the storm, but th^s was later cleared away by falling 

 rain. Many of the birds became exhausted from continuous flutter- 

 ing about the lights and later succumbed to exposure, but the death 

 of the majority w..s caused by dashing into the structures. The 

 Maryland yellowthroat suffeiad the greatest mortality, Mr. Culver 

 recovering 130 of this species of which three -fourths were females. 

 This sex ratio was due to the lateness of the season, as the males are 

 the first to migrate. Culver also reports that during a migratory 

 wave, October 17 and 18, 1915, the yellowthroat was again killed in 

 large numbers, the tctal being exceeded only by that of the myrtle 

 warbler. 



Robert Overing (1938) on September 12, 1937, between 10 : 30 p. m. 

 and midnight identified 576 individuals of 24 species which struck 



