Feeding ecology drives lead exposure of facultative and obligate avian scavengers in the eastern United States

Environmental Toxicology and Chemistry
By: , and 



Lead poisoning of scavenging birds is a global issue. However, the drivers of lead exposure of avian scavengers have been understood from the perspective of individual species, not cross‐taxa assemblages. We analyzed blood (n = 285) and liver (n = 226) lead concentrations of 5 facultative (American crows [Corvus brachyrhynchos], bald eagles [Haliaeetus leucocephalus], golden eagles [Aquila chrysaetos], red‐shouldered hawks [Buteo lineatus], and red‐tailed hawks [Buteo jamaicensis]) and 2 obligate (black vultures [Coragyps atratus] and turkey vultures [Cathartes aura] avian scavenger species to identify lead exposure patterns. Species and age were significant (α < 0.05) predictors of blood lead exposure of facultative scavengers; species, but not age, was a significant predictor of their liver lead exposure. We detected temporal variations in lead concentrations of facultative scavengers (blood: median = 4.41 µg/dL in spring and summer vs 13.08 µg/dL in autumn and winter; p = <0.001; liver: 0.32 ppm in spring and summer vs median = 4.25 ppm in autumn and winter; p = <0.001). At the species level, we detected between‐period differences in blood lead concentrations of bald eagles (p = 0.01) and red‐shouldered hawks during the winter (p = 0.001). During summer, obligate scavengers had higher liver lead concentrations than did facultative scavengers (median = 1.76 ppm vs 0.22 ppm; p = <0.001). These data suggest that the feeding ecology of avian scavengers is a determinant of the degree to which they are lead exposed, and they highlight the importance of dietary and behavioral variation in determining lead exposure. 

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Publication type Article
Publication Subtype Journal Article
Title Feeding ecology drives lead exposure of facultative and obligate avian scavengers in the eastern United States
Series title Environmental Toxicology and Chemistry
DOI 10.1002/etc.4680
Volume 39
Issue 4
Year Published 2020
Language English
Publisher Society of Environmental Toxicology and Chemistry
Contributing office(s) Forest and Rangeland Ecosystem Science Center
Description 11 p.
First page 882
Last page 892
Country United States
State Alabama, Georgia, Maryland, New Jersey, New York, North Carolina, Pennsylvania, Tennessee, Virginia, West Virginia
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