Bad News for Wild Condor Chick at Pinnacles National Monument

Condor and egg.

The hatching of a California condor egg was big news at Pinnacles National Monument earlier this year. Photo by Gavin Emmons, National Park Service

The birth of a chick earlier this year to a pair of nesting California condors was cause for celebration at Pinnacles National Monument, but scientists tracking the health of the young bird have bad news. Due to extremely high levels of lead in its blood, it's been necessary to evacuate the bird from its nest to a specialized facility for intensive treatment.

Condor biologists at Pinnacles National Monument and Ventana Wildlife Society tracking the health of the young wild condor discovered the problem last week. Park Service biologists then trapped the parent male, condor 318, and discovered he also has toxic levels of lead in his blood.

The adult condor was immediately taken to the Los Angeles Zoo for chelation (a treatment to remove lead from the body) while the 50-day old chick was treated by veterinarians and condor biologists in the nest during early morning climbs into the rocky cliff cavern. Chelation is a process used in condors in which calcium EDTA, a chemical that binds with heavy metals, is injected into the animals to prevent retention of lead in the tissues.

Although the adult female continued to care for its young and the nestling received several emergency chelation and hydrating fluid injections, the young condor’s health continued to decline. As a result, biologists decided yesterday that, for the survival of the nestling, it needed to be evacuated to a facility where it could receive more intensive care.

National Park Service and Ventana Wildlife Society biologists are trying to trap the adult female of this pair to determine if she too has been exposed to lead. This condor nest was the first inside Pinnacles National Monument since re-establishment efforts began there in 2003 and the first documented successful hatching of a condor in the park in over one hundred years.

Lead poisoning has been an on-going problem for condor populations. Condors are exclusively scavengers, feeding on a wide range of dead mammals. Research has established that the principle source of lead exposure among condors is lead ammunition.

Lead Ammunition has been banned for the taking of big game in parts of central and southern California, although that move has been a controversial one for some hunters. Park officials note that shooters who have made the switch to non-lead ammunition have made an invaluable contribution to the health of scavenging wildlife.

News about the park's nesting pair of condors attracted considerable attention earlier this year. According to the park, hundreds of visitors over the past two months have enjoyed the rare opportunity to witness an active condor nest in the wild. Pinnacles National Monument will keep the temporary closure area around the nest in place until biologists determine whether the nestling can be returned to the wild.

If you'd like more information about the condor program at Pinnacles, you'll find details on the park website.

Comments

The reference link above linked to the statement "...Research (that) has established that the principle source of lead exposure to condors is lead ammunition..." refers to a study, Church et al (2006).

That study was discredited in front of the California Fish & Game Commission in a hearing on August 6, 2009. Evidence was presented to the public record showing that Church et al ignored data from it's own reference bibliography, and excluded condor blood lead data and isotopic ratio measurements that fell outside of the narrow range the authors presented as representing the lead isotopic composition of lead ammunition.

Production of this and other data, and the continuing omission of key (and contradictory) information was an important aspect as to why the California Fish & Game Commission rejected expanding ammunition bans in "Condor Country" to include lead bird shot for upland game and small mammal hunting.

In a 4-1 vote, Commissioners voted down the proposed ban. Commissioner Richard Rogers even stated for the record during various hearings that he thought that much evidence previously presented as linking lead ammunition to condor blood lead levels may be "...pseudo science...".

Please reference the various hearings of the California Fish & Game Commission on June 24, 25, and August 6, 2009 for the discussions involving the evidence presented regarding the inaccuracies in Church et al (2006).

These can be found at:

http://www.cal-span.org/cgi-bin/media.pl?folder=CFG

Today virtually all Earth's species have non-naturally occurring chemicals in their makeup because of one kind of pollution or another, and humans are responsible. I wonder what humans will look like in the future? Maybe we'll be made of plastic.

Anonymous -

Thanks for your perspective on one of the studies about lead poisoning in the condors and lead ammo. As I mentioned in the story, the question of lead ammo's impacts on wildlife has been the subject of some controversy.

In response to your concerns, I revised the link in the story to point to a page on the park website that links to a number of studies world-wide on the effects of lead ammunition on wildlife, including condors. There's also some interesting discussion on that site about possible human risks from lead ammo.

I'm certainly not an expert on the subject, but given the information in all those additional studies on the impacts of lead ammunition on wildlife and the condor's diet of carrion, it would be interesting to hear other plausible, research-backed, explanations for the high levels of lead in the birds.

Thank you for the link to a study presented at the 2008 Peregrine Fund Symposium on Lead.

As for other sources of lead in the environment, one that I have always found fascinating was from the testimony of Dr. Don Smith of UC Santa Cruz to the California Fish & Game Commission from July of 2007.

Dr. Smith noted that scientists at UC Davis were tracking lead toxicosis in dairy and range cattle. A surprisingly high number of cattle were indicated by Dr. Smith to have died due to lead toxicosis (something on the order of .5%, apparently), and were found to have liver lead levels in the 20-40 ppm range (he did not indicate whether that was a "wet weight" or "dry weight" figure.).

It has never been proven nor observed in the literature that cattle have been known to ingest carrion shot by hunter, poachers, and depredation permittees, so it begs the question as to what the particular sources of lead to cattle, and possibly other herbivores, is that could also result in such elevated lead levels.

In condors and other raptors, 20-40 ppm liver lead levels have been associated with lead toxicosis and mortality by some.

Also, if a condor were to come across a cattle carcass in it's range where the animal had died due (or with) to lead toxicosis at 20-40 ppm liver lead, the source of liver or kidney contaminated with such levels is something that would appear comparable to the "small fragment" hypothesis postulated in Hunt et al (2006).

If a condor were to consume approximately 1/2 kilograms of cattle liver contaminated with 20-40 ppm lead, the condor could possibly consume 10-20 mg of lead which would also be in a most soluble or "bioavailable" form.

10-20 mg of lead is roughly comparable to about 1/2-1% of the mass of a standard 150 grain deer bullet made with lead. A one per-cent "sized" fragment of such a bullet would be a radiographically visible object by comparison, but where 10-20 mg of lead in the liver may not be radiographically visible.

This is just one possible source of environmental lead available to condors and other scavengers. Dr. Fry's 2003 study, while focused primarily on lead ammunition, did note quite a number of other environmental lead sources that have gotten short shrift from the various participants in the Condor Recovery Team.

Perhaps if they will not investigate such other threats to condor recovery, perhaps others will take up the "slack".