Study confirms ammunition as main source of lead poisoning ...( d the ammunition that these birds are m...)

d the ammunition that these birds are most likely to encounter in the remains of hunted game, and we found that lead from those sources can account for the lead in the blood of 77 percent of the birds tested," said Church, who undertook the study after spending a summer monitoring condors as a volunteer with the Ventana Wildlife Society.

The researchers obtained blood samples from 18 free-flying condors in central California and 8 birds that had been raised in captivity and were still in holding pens waiting to be released. At the time of the study, this sample represented 43 percent of the wild condor population in all of California.

The lead levels in the blood of prerelease condors were low, and the lead was isotopically similar to background lead in the California environment. In the free-flying condors, however, blood lead levels were higher and the lead had a different isotopic composition that approached the composition of the lead in ammunition. In the most severely lead-poisoned birds, the blood lead matched exactly the composition of the lead in ammunition, Smith said.

"We found that in the birds with elevated blood lead, the lead isotope ratios fit a mixing model in which one source of lead is the background environment and the other source is ammunition. The results show that lead ammunition in animals shot and left in the field is the predominant source of lead exposure in condors," he said.

Kelly Sorenson, executive director of the Ventana Wildlife Society, said the study provides a solid basis for efforts to resolve the problem of lead exposure in condors. Possible solutions range from legislation limiting the use of lead ammunition to voluntary programs to encourage the use of alternative ammunition in areas where condors are known to scavenge for food, he said.

"There are different ways to get at this problem, but no matter how it is resolved in California, this research was desperately needed not
'"/>

Contact: Tim Stephens
stephens@ucsc.edu
831-459-4352
University of California - Santa Cruz
30-Aug-2006

Page: 1 2 3
Related biology news :

1. Study begins to reveal clues to the cause and progression of sepsis
2. Study finds gender differences in renal and other genes contributing to blood pressure
3. Study suggests estrogen deficiency can lead to obesity-induced high blood pressure after menopause
4. Study: Sticking to the sand might not be such good, clean fun for beachgoers
5. Study points to new way to predict death risk from torn aorta
6. Study identifies new gene therapy tools for inherited blindness
7. Study finds contaminated water reaching Floridas offshore keys
8. Study sheds light on why humans walk on two legs
9. Study explains how pathogens evolve to escape detection
10. Study finds hereditary link to premenstrual depression
11. Study identifies energy efficiency as reason for evolution of upright walking