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PACIFIC SOUTHWEST REGION: California Condor Summer Work-Ups
California-Nevada Offices , July 28, 2014
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Volunteer holds a California condor as blood is removed for lead testing.
Volunteer holds a California condor as blood is removed for lead testing. - Photo Credit: Jon Myatt/USFWS
A high mountain valley encircled by deep canyons, steep ridgelines, and rocky pinnacles, Hopper Mountain National Wildlife Refuge is the gateway into California condor country
A high mountain valley encircled by deep canyons, steep ridgelines, and rocky pinnacles, Hopper Mountain National Wildlife Refuge is the gateway into California condor country - Photo Credit: Jon Myatt/USFWS
Wildlife Biologist Geoff Grisdale applies pressure after taking a blood sample as Condor Program volunteer Gabriela González-Olimón holds the condor.
Wildlife Biologist Geoff Grisdale applies pressure after taking a blood sample as Condor Program volunteer Gabriela González-Olimón holds the condor. - Photo Credit: Jon Myatt/USFWS

By Cindy Sandoval

As June nears biologists at Hopper Mountain National Wildlife Refuge start planning the annual California condor summer work-up event. During the work-ups endangered condors are trapped so that biologists can examine each bird, change transmitter and GPS devices attached to the bird and test for lead poisoning.

During the months of June and November, U.S. Fish and Wildlife Service (Service) staff bait a large enclosure on the refuge with the carcass of a calf and wait for the condors to arrive. The California condor is the largest bird in North America with a wing span of about 9 feet and feeds solely on dead animal carcasses known as carrion. As the birds enter the enclosure to feast they are trapped in the large coop which contains branches for them to perch on and a small watering hole. Once the birds are inside the enclosure, biologists start isolating the animals so they can be transported inside an adjacent building to await Service staff and volunteers. During this summer’s work-up Service staff were joined by volunteers from the Santa Barbara Zoo and National Wildlife Federation to help biologists with condor care, lead testing and recording measurements.

After the condors are caught and brought inside, a three person team handles each condor so that the birds head, feet and wings are immobilized. A Service biologist will then sanitize the condor’s leg and draw blood to test for lead. The lead test is conducted on site and only takes a few minutes. A tiny beep indicates when the test is complete. On this day of summer work-ups, the first condor tested, #489 had a blood lead level of 61 micrograms per deciliter, over the 35 micrograms per deciliter lead limit for condors. When condors are determined to be suffering from lead exposure they are transported to the Los Angeles Zoo for treatment and California condor #489 was placed in a large animal create to await a trip down to the zoo.

Eleven other condors were tested during this day of work-ups and these birds were all under the blood lead limit. “The most common source of lead poisoning in California condors is ingesting lead bullet fragments left in carcasses,” said condor biologist Laura Mendenhall. Mendenhall explained that when a lead bullet strikes an animal it fragments into tiny pieces that remain in the body and a feeding condor is unable to distinguish lead laced meat and clean carrion.

Lead poisoning in condors can have both neurological and physical effects. If the condor does not receive medical attention it can suffer weight loss, lethargy, blindness and death. According to the Peregrine Fund, a California condor suffering from severe lead poisoning can experience digestive system paralysis. The bird is unable to pass food or water through the digestive system. Feeling hungry and dehydrated the bird will continue to forage for food, despite the fact that it has a full crop. The crop is an expanded, muscular pouch near the throat that is used to temporarily store food in birds. When a crop is full but does not move food through the digestive system the condition is known as crop-stasis and it can be deadly.

Luckily for condor #489, the lead exposure was caught early and it will undergo lead poison treatment at the Los Angeles Zoo that will last one to two weeks. During that time the large bird will be treated with an intravenous medicine to bind the lead and help flush it from the condor’s body. After the condor’s lead level is lowered, the bird will be released back at the refuge. “It is not uncommon for us to send at least one or two birds to the zoo for treatment during these work-ups. In 2013 alone we sent 25 birds to the zoo for lead treatment," added Mendenhall.

The California condor has come a long way since first being listed as endangered in 1967. “There were only 22 California condors in the world in the early 1980s, today there are over 400 birds, some in zoos and others in wild populations,” said Service biologist Joseph Brandt. While the numbers of birds is impressive the iconic species still faces the threat of lead. Beth Pratt, California Director of the National Wildlife Federation, a work-up volunteer added “What we are doing here in California, is getting people engaged with the wonderful wildlife we have here and how they can help. Without people doing their part and trying to eliminate condor lead exposure this reintroduction may not ultimately be successful.”

In recent years there has been a push to eliminate lead in California. Governor Jerry Brown signed A.B. 711 into law in California banning lead ammunition for hunting; this statewide ban takes effect in 2019. There are non-lead bullets on the market made of copper or copper alloys that serve as an alternative to lead bullets. Hunting, when done with non-lead ammunition, actually benefits California condors and assists in their recovery by providing additional food sources like unrecovered animals and gut piles.

The California condor population numbers have improved greatly thanks to the hard work and dedication of the Service, volunteers, California zoos and hunters that have switched to non-lead ammunition. With condor parents raising new chicks every year the population should increase as these iconic birds continue their recovery.

Cindy Sandoval is a public affairs specialist at the Pacific Southwest Regional Office in Sacramento.


Contact Info: Cynthia Sandoval, 916-978-6159, cynthia_d_sandoval@fws.gov



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