Hunters Asked To Assist In Condor Recovery Effort

Send by email Printer-friendly version Share this

State and federal wildlife experts are asking hunters to help with the California condor recovery effort by taking voluntary steps to reduce the potential exposure of condors to lead ammunition. Two recently released reports independently conclude that lead ammunition is contributing to the high lead levels documented in some wild condors. Both reports conclude that more studies are needed to identify and remove all sources of lead contamination in the birds.

One report, an Assessment of Lead Contamination Sources Exposing California Condors, was commissioned by the DFG to obtain an independent analysis of the available data on lead in the environment in California and to assess the magnitude of the lead exposure hazard to condors. The report was prepared by Dr. D. Michael Fry of the Department of Animal Science at UC Davis. (The complete report is available on the DFG Web page, at: http://www.dfg.ca.gov/hcpb/info/bm_research/bm_pdfrpts/2003_02.pdf)

A report prepared for the U.S. Fish and Wildlife Service (FWS) from the California Condor Lead Exposure Reduction Steering Committee - which includes a diverse group of hunters, conservation groups, and wildlife conservation agencies - states that an increasing number of condors are being exposed to lead, and in greater amounts. The report said, "Further, there is a strong tendency for the toxicity events to occur in the fall of the year, roughly coinciding with hunting seasons, although episodes, clearly involving lead ammunition, have occurred at other times of the year also." (A complete copy of the Steering Committee report can be obtained from the FWS by calling 805-644-1766.)

The Steering Committee has issued the following recommendations to people who hunt in condor range: " Retrieve all killed animals (including coyotes and small game) from the field, or
" Hide carcasses or gut piles by burying them, covering them with brush or rocks, or placing them in an inaccessible area, or
" Remove bullets and surrounding impacted flesh when leaving carcasses or gut piles in the field, or
" Use lead-free ammunition, in which case none of the above is needed

"Hunters are our long-time partners in wildlife conservation," said Sonke Mastrup, Deputy Director of the DFG's Wildlife and Inland Fisheries Division. "We are confident that we will see a high percentage of hunters who voluntarily comply with the recommendations."

"We realize lead and condor mortality is a significant challenge, and we're all pulling together to come up with effective solutions," said Steve Thompson, manager of the FWS's California/Nevada Operations Office. "Working with hunters to reduce the risk of lead exposure to California Condors will have to be an important part the solution."

Dr. Fry's report cites extensive hunting within the condor range, and estimates the number of carcasses or partial remains left in the field at more than 30,000 annually. "The risk of lead exposure to condors is high, because of the amount of carrion left in the field," the report stated. "Direct observations of condors feeding on hunter-shot carrion are few, even with intense radiotelemetry and visual surveillance, and every effort should be made to document and organize the field observation data to quantify the exposure hazard from hunter-shot carrion."

The report states that lead in blood does not accumulate over time, but drops quickly when exposure is terminated. The rate of exposure in condors in southern California indicates that they are exposed to lead frequently. Dr. Fry recommends using a technique known as mass spectroscopy to measure lead that is deposited at points along a growing feather, so that the history of exposure of each bird can be determined.

"The report highlights the need for additional studies because there simply isn't enough information to document the source of every incidence of lead exposure in condors," said Ron Jurek, a DFG biologist and member of the Condor Lead Exposure Reduction Steering Committee.

Condor recovery experts have systematically monitored lead exposure in condors since 1997. Five condors have died of lead poisoning since 1997-one in California, one in Utah, and three in Arizona. An additional 26 condors have received emergency chelation treatment to reduce toxic lead levels. The source of lead has been identified in some cases as spent ammunition in the form of both shotgun pellets and fragments of rifle bullets.

The Steering Committee felt it was prudent to take steps to eliminate ammunition as a source of lead in condor range. "When you're dealing with an endangered species, even one death is significant," said Jurek.

There are several alternatives to lead ammunition on the market today and more alternatives are being developed.

Fry's report identified four potential sources of lead in the environment that could impact condors: lead fragments in carcasses of shot animals; residues in calf carcasses used in condor feeding programs; lead emissions to the atmosphere; and lead in soil from natural sources, metals deposited by people, or deposits from the air. He recommended that work beundertaken to determine amounts of lead from soil sources, such as rifle or military ranges, and in tissues of deer and other herbivores that inhabit the area.

The current population of condors now stands at 221. The California condor range includes the California mountains bordering the San Joaquin Valley; northern Arizona and southern Utah; and northern Baja California. Adult condors may travel up to 150 miles in a day to forage for food. Detailed population information can be found on the Condor Population Status Web page, at: this site.

The California Condor Lead Exposure Reduction Steering Committee is a subcommittee of the California Condor Recovery Team, which serves in an advisory capacity to the U.S. Fish and Wildlife Service. The lead steering committee is comprised of: The Raptor Center, Cirrus Ecological Solutions, the Wildlife Management Institute, The Peregrine Fund, the National Audubon Society, Safari Club International, the National Rifle Association, the National Shooting Sports Foundation, Hawk Watch International, the San Diego Zoo, the California Department of Fish and Game, the Arizona Department of Game and Fish, and the U.S. Fish and Wildlife Service.