Feeding Ecology Drives Lead Exposure of Facultative and Obligate Avian Scavengers in the Eastern United States.

Abstract

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. Environ Toxicol Chem 2020;39:882-892. © 2020 SETAC.

• Authors: Vincent A Slabe, James T Anderson, Jeff Cooper, Tricia A Miller, Bracken Brown, Anna Wrona, Patricia Ortiz, John Buchweitz, Dave McRuer, Ernesto Dominguez-Villegas, Shannon Behmke, Todd Katzner
• Journal: Environmental toxicology and chemistry (Environ Toxicol Chem) Vol. 39 Issue 4 Pg. 882-892 (04 2020) ISSN: 1552-8618 [Electronic] United States
• PMID: 32022303 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)
• Copyright: © 2020 SETAC.

Chemical References

• Environmental Pollutants
• Lead

Topics

• Animals
• Bird Diseases (chemically induced)
• Diet
• Ecology
• Environmental Exposure (analysis)
• Environmental Pollutants (analysis, toxicity)
• Female
• Lead (analysis, toxicity)
• Lead Poisoning (veterinary)
• Liver (chemistry)
• Seasons
• Species Specificity
• United States