"As we pushed off (in our boat) for 

 the ride home, the adult pelicans tightened 

 their circle to a funnel," she writes. "With 

 each pass, a few more dropped to the 

 ground to soothe their young and 

 regurgitate fish. By the time we reached 

 the channel that led to the public dock, 

 only a few birds remained in the air. The 

 rest had settled like dust from the still air 

 of a summer day." 



Banding operations like the one 

 conducted by Weske have helped 

 scientists track the routes of pelicans, 

 which are migratory birds. Some species 

 have migrated as far as south of the 

 equator. 



"They're migratory birds, but some 

 migrate and some choose to stay here 

 during the winter, especially if it's mild," 

 Parnell says. "Chicks that have been 

 banded here have been returned to us 

 after having died as far south as Cuba." 



Some scientists have linked the 

 drastic decline of brown pelicans 20 years 

 ago with man's efforts to eradicate 

 mosquitoes and other insects from coastal 

 areas. 



The use of DDT-laden pesticides in 

 more southern states such as Texas and 

 Louisiana — where the pelican is the state 

 bird — in the 1950s and 1960s caused 

 pelicans and other carnivorous birds, like 

 ospreys and peregrine falcons, to lay thin- 

 shelled eggs. 



Those eggs stood an unlikely chance 

 of hosting a healthy bird, Parnell says. 

 Thus, pelican populations in Texas were 

 almost eradicated. 



In North Carolina, where there had 

 been no evidence of thinner eggs, DDT 

 was sprayed along the Outer Banks in 

 mosquito removal programs. 



"We've never really linked DDT to 

 the decline of the pelican here," Parnell 

 says. "But it may have been a factor." 



DDT-laden pesticides were banned in 

 this country in the late 1960s. But that 

 event may not be the single most impor- 

 tant factor in the rise in pelican popula- 

 tions. 



"I don't think pesticides are an issue 

 and haven't been an issue here," Parnell 

 says. "I've never seen thin eggs and that 

 kind of thing." 



12 JANUARY/FEBRUARY 1992 



