Posted Tuesday, 23 February 2010 09:50
BOISE, IDAHO — After three years without a confirmed mortality from lead poisoning, three California condors have recently died from the biggest challenge to the species' recovery. The condors, including a female and her chick from the previous year, were recovered by The Peregrine Fund.
Photo by Lynn Chamberlain
Necropsies to determine the cause of death were performed at the San Diego Zoo's Institute for Conservation Research. Testing confirmed the presence of lead fragments in the digestive tracts of all three birds. Lead shuts down the condors' digestive system, which leads to starvation, weakness and death.
"While the deaths of a breeding female and her wild-hatched chick are a significant loss, condor conservation has been gaining ground since lead poisoning was first identified as a leading cause of mortality and we began to educate hunters about the effects of spent lead on condors," said biologist Chris Parish, head of The Peregrine Fund's condor recovery operation in Arizona. "But, as the condor recovery program progresses, new challenges have been identified."
The three dead birds had been outfitted with tracking equipment that allowed field biologists to monitor daily movements. In recent years, that radio tracking data has identified increased use of southern Utah as a major foraging area for the flock.
"When we first reintroduced condors to northern Arizona in 1996, the birds primarily foraged closer to home," said Chris Parish. "Now that we have observed the condors expanding their range into Utah and foraging more frequently outside of the local release area, conservation partners are working with Utah and its hunters to reduce the amount of spent lead ammunition available to condors in gut piles and carcasses left in the field."
The Peregrine Fund tries to capture all condors twice yearly to test for lead exposure, the leading cause of condor death. Birds with high blood lead concentrations are treated with chelation therapy to reduce the lead in their system. Condors are scavengers and research in the last five years has proven that they consume tiny fragments of lead in the remains of gunshot animals.
To aid condor conservation, the Arizona Game and Fish Department started a non-lead ammunition outreach program in 2003 to hunters drawn for hunts in the condor's core range. Surveys show that 85 percent of hunters took voluntary measures in 2009 to reduce the amount of available spent lead ammunition in the condor's core range.
Now the Utah Division of Wildlife Resources is implementing a similar program for hunters on the Zion unit in southwestern Utah.
"We've started educating our hunters about the effect that lead ammunition has on condors," said Jim Parrish, nongame avian coordinator for the Utah Division of Wildlife Resources. "The next thing we're going to do is give everyone who hunts on the Zion unit a coupon for a free box of non-lead ammunition."
"There's no reason to reinvent the wheel, so we're modeling the Utah program after Arizona's non-lead effort," continued Jim Parrish. "Utah's sportsmen are conservation-minded. We're confident they'll step up to the challenge and that our program, combined with the highly successful program in Arizona, will keep the condor population healthy and allow it to grow."
Condor conservation partners include The Peregrine Fund, Arizona Game and Fish Department, Utah Division of Wildlife Resources, Utah Wildlife in Need, Bureau of Land Management, National Park Service, U.S. Fish and Wildlife Service, and U.S. Forest Service.
For more information on condor conservation and non-lead ammunition, visit www.peregrinefund.org or wildlife.utah.gov/condors.
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