Seven of the 80 wild condors that soar over the Grand Canyon and surrounding areas have died since December. Three of the deaths have been conclusively linked to lead poisoning from ingesting spent lead ammunition fragments in carrion. Lead poisoning is also suspected in the other four deaths.

California condor. (Photo: Daniel George)

California Condors are the largest birds in North America, and one of the most endangered, protected animals in the U.S. Barely more than 400 are known to exist both in the wild and in captivity. Nearly half the birds reintroduced into Utah and Arizona since 1996 have died or disappeared. The leading cause of death is lead poisoning caused by eating carrion killed by hunters using lead bullets and shotgun pellets.

Lead poisoning is said to affect several other species, including the golden eagle and the turkey vulture, but affects the condor in particular, as they eat more and have powerful digestive systems that quickly dissolves lead which leaches into their bloodstream. The animals feel the effects within days. Lead poisoning paralyzes the digestive system often killing the animal slowly through starvation. Ingested lead is dangerous even at extremely low levels.

The research

linking lead poisoning in condors to lead from spent ammunition is conclusive. Case in point: a 10 year-old male condor (#318), found inland from Big Sur in west/central California on a ranch near Pinnacles National Park, last November. The bird was barely alive and unable to feed or use its legs to stand. Veterinarians could not save it. A necropsy determined the cause of death was lead toxicosis. A radiograph showed multiple metal fragments and a bullet-shaped object in the digestive tract. The object was removed and found to be a .22 caliber lead bullet.

Radiograph of condor #318 with lead bullet. (Photo: Ventana Wildlife Society)

    The death of condor #318 was a huge loss for the central California population. The bird was a breeding male, the first at Pinnacles National Park in more than 100 years. With only a few breeding pairs established in the region, his loss leaves a void which might not be quickly filled. His surviving mate has left the breeding territory and it is not clear if and when she will pair with another condor and breed again. The loss of even a small number of breeding pairs, and the offspring they produce, puts the entire population at risk.

    Volunteer efforts to reduce lead ammunition around the Grand Canyon aren’t getting the job done. Most of the remaining wild Grand Canyon condors need regular, emergency blood treatment for lead poisoning to save their lives.

    About two dozen states have partial bans on hunting with lead bullets and/or shot, mostly in sensitive wildlife refuges. In California, hunting with lead bullets is prohibited in eight counties. In 2007 California passed AB 711 which banned the use of lead ammo for hunting in the roosting and scavenging territories of the condor, but the birds are still dying from ingested lead. The continuing mortality of the birds has California activists and legislators once again considering banning the use of lead ammo for hunting. A bill has been introduced to make the ban statewide. The new bill, which is expected to pass, would expand AB 711 to the entire state. A similar bill to ban the use of lead ammo for hunting was shot down in 2010. The EPA similarly rejected a nation-wide lead ammo ban in 2010.

    California condor: (Photo: The Peregrine Fund)

    The U.S. Geological Survey estimates that nationwide there are 400,000 pieces of lead shot per acre in wild game territory that can be eaten or washed into waterways, and that the 60,000 metric tons of lead fired off in 2012 is second largest use of lead behind storage batteries.

    Lead is by far the leading cause of death for the remaining 234 California condors left in the wild.


    Source: Center for Biological Diversity and Ventana Wildlife Society.

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