Condor of California

The Condor of California ( Gymnogyps californianus ) is large a Oiseau Charognard which lives on the Western coast of the the United States.

With its 1 m 40 of length and 2 m 80 of scale, it is the second largest bird of the world. In terms of weight, it competes with the Condor of the Andes with 11 to 13,5 kg. Although robust and counting only few Predatory S, its species failed to die out in 1985. Only 9 individuals survived in 1994, and only in California. It was saved in extremis by the breeding in captivity (artificial egg incubation and breeding of young people, with provision of meat for the young people), which allowed an attempt at reintroduction in the nature, made difficult because of an extreme exposure to the Saturnisme. It nevertheless showed a certain success since we add up 128 today of them.

Its Life expectancy is normally 50 years, and become adult, he lives in couple durable monogamist. Its Gestation is exceptionally long: 2 years, just as the care granted to small.

Distribution

One formerly found it in almost all the North America; Colombia-British with the California and the Florida. The surface of current distribution is that of the zones of attempt at reintroduction; mountains of California and Nord of Arizona.

Behavior

This bird, which can make long voyages to nourish itself, fulfilled an ecological and medical function essential, near to that of the vultures, by nourishing Charogne S or remainders of carrions of Bison S, stag S, dash S, etc killed by the Loup S, lynx, Couguar S, Coyote S or by the men. After the regression of the bisons massively killed by the colonists, the corpses of cows and sheep became important in its food, with the animals mortally wounded with hunting or by vehicles (Roadkill) and not recovered by the hunters or the squaring.

Threats and causes regression

Although its Plume S was used for the ornaments, it does not seem to have suffered from hunting by the Amerindian S. It is with the arrival of the pioneers that it brutally regressed to become rare in the middle of XIX^e century and very rare in XX^e century, because of hunting, of the egg collections, and because of the poisoned soft foods laid out by the stockbreeders against the predatory ones, but also because of the industrialization of the agriculture which deprived it of the large carcasses of which it was nourished. It is possible that it locally suffered from industrial pollution (mercury, lead.), but it is especially the intoxication by the Plomb of hunting which seems to be become its first cause of disappearance. The Condor of California indeed eats the corpses while generally starting with the wound consisted the entry of the ball when the animal was killed or wounded with hunting). There can also introduce the balls which remained in the corpse, which explains why although the efforts to reduce lead in the environment were more important and earlier in North America than in Europe, lead poisoning remains the first cause of mortality of the adult condors. The majority of the birds are poisoned only by the lead shot, but the large birds such as swans or condors are regularly victim of acute poisoning by ingestion of lead or lead bullets (turlutte and other tackles) of fishing (for the swan). The zone of reintroduction (Big On) is polluted little and one of is driven out west of the the United States. The exposure to the lead of hunting was thus judged there to be a weak Risque for the condors. But the observation on the ground, by Radiotracking and satellite showed that if the young people agreed to nourish corpses " propres" brought by the men in the vicinity, the adults, they, could consume Cadavre S of stags common into the county of the South-Monterey to north and in the county of Obispo San Luis to the south, where the deer tribe is still driven out with - generally - Munition S with lead. Lead bullets or fragments of balls (sometimes improperly named " Shrapnel S " in reference to the glares of shell of the First World War) present in the Carcasse S of common stags is the probable cause of this lead poisoning.

One knows for a long time that the raptors located at the “top” of the food Pyramide are particularly touched by lead poisoning related to the indirect ingestion of lead of hunting or of fishing (100% of 100 harriers of the reeds tested in large France in two wetlands were reached of acute lead poisoning), the fishing Aigle North-American is also often victim of lead poisoning induced by hunting and fishing, but, the condors is probably even more sensitive to lead than the other raptors, because they do not régurgitent the indigestible feathers, bones and other fragments and objects which they eat. However, at the majority of the birds, the feathers, but especially as in the mammals, the bones fix and accumulate introduced lead and not excreted (80% of this lead are stored in the bones). The high acidity of its gastric juices facilitates the fast passage of lead in its blood.

Program reintroduction

It was initiated in 1992 by the Federal government and several ONG (of which Wilderness society) whereas the number of individuals (always maintained in zoos) was considered become sufficient to try to reconstitute two cores of population, one in California of the South, the other in the north of Arizona, each one starting from 150 individuals, including 15 couples raising small.

Difficulties: Many the birds slackened in good health after acclimatization died quickly, almost always for the reasons which recently led to the general decline of the populations of the condor and other birds; by intoxication by the lead of the Ammunition S, and this, for the adults, in spite of an offer in healthy food those which work with its reintroduction.
Quatre of the condors reintroduced in Arizona and one of those of South-California died of acute lead poisoning in 2001. And several other dead birds and not found in California of north could also be dead of lead poisoning.
Depuis 1997, the reintroduced birds are followed by blood tests. 13 of them had to undergo a continuous medicamentous treatment for intoxication by lead (Chélateur S).
Les remainders of the corpses of 40 others of the condors slackened in nature were found between 1993 and 2002, victims of collisions with electric lines or were eaten by eagles or coyotes, or after a death whose causes remained unknown. These remainders being very degraded, they were not the subject of lead analysis, but it is possible that lead is - at least for certain cases - a factor responsible for their untimely death.

History of the reintroduction

17 Condors were reintroduced in the zone of Big On (mountainous area Littoral 150 km length E on the Caldera of California), in a wild zone, low in sources of Pollution and little attended by the hunters and thus a priori among less contaminated lead (Grenaille) of hunting. They are controlled every 6 months. They had at the beginning of the experiment of the Plombémie S lower than the average and than elsewhere. However, at the end of 2002, one of the 17 Condors of California reintroduces by Ventana Wilderness Society had to be neat for acute lead poisoning and 7 of his/her companions (on 9 analyzed) presented plombémies characteristic of a chronic lead poisoning, but allowing however according to the Vétérinaire S that one slackens them in the zone of reintroduction. Recall: the plombemy translates only the recent contamination. Only an analysis of lead in the Os and the Foie would have made it possible to evaluate the exposure to a chronic Intoxication, but it cannot be done without affecting the integrity of the bird or exposing it to radiations.

The Plomb is a very soft Métal which erodes and is solubilized very quickly in contact with the gastric juices when it is not a question of large pieces. The Plomb Neurotoxique can paralyze the digestive Système then muscular of the vultures. However lead was prohibited only in the Grenaille and that in certain countries or that in the wetlands. In 2006, the shooting with ball of lead remains the rule for big game and the lead of fishings remains used almost everywhere (it poisons the swans regularly which can be consumed by the vultures and condors). This lead remains one of the principal threats for the survival of the species according to the Ventana Wilderness Society .

When a Condor presents the Symptôme S of lead poisoning, it is radiographed. So remainders of balls or lead shot are visible in the gizzard, after injections of Chélateur S making it possible to decrease the absorption of lead and by facilitating the excretion, the lead remainders are extracted with the assistance from an endoscope. If the intoxication is serious, the bird is kept in convalescence in Monterey County SPCA (especially created to treat the Saturnisme in the bird) before being slackened and rehabilitated with the flight in an external enclosure in Big On.

Lead poisoning; worsening factor of other causes of mortality

Lead is source of Anémie. Neurotoxic, it affects the Intelligence, the Vigilance and the Comportement of the birds, by decreasing their reflexes and their skill in flying well. For this reason, risks of died by predation and collision with vehicles (Roadkill) or with electric cables or various superstructures (pylons, antennas, bridges, panes, etc) increase in the birds poisoned by lead. Lead is most probably, in the bird as at the man, a source of increased failure of the reproduction, of reduction in the Immunité and thus in the '' fitness '' (shown in experiments at the Canard Colvert).

To deal with the problem with the source…

The Wilderness Society launched a training program, sensitizing and action against the avian Saturnisme (acute or chronic) towards associations of hunting and shooting, the ranches private, the arms manufacturers and sport stores, with distribution of thousands of booklets on the less toxic ammunition. In 1999, she finally convinced several owners of ranches of California of north to replace their lead bullets by a new ball less-poison (tungsten) when they must kill out of the sick or wounded cattle (Rem: these animals could also be deadened and killed without use of toxic product or remanent, but the use of firearms is a social phenomenon particularly anchored to the USA).

Food of substitution

Clean” and controlled food a “is offered to the Condors. Owners of local ranches sound also invited to offer their calves still-born children, considered to be a priori “clean” (from the content point of view lead). Not to accustom the condors with the man, these corpses are brought night, are packed in plastic near the lodgings. However the experienced adults leave instinctively more and more far to go to seek themselves their food.

Elimination of the sources of risks

The foundation invites the hunters to deeply bury the remainders and the Abat S of animals killed with hunting, and to seek and complete the wounded animals, which is in addition recommended for medical reasons (of which by fear of diffusion of the spongiform encephalopathy with request (Chronic wasting desease or CWD) which develops at the Cervidé S in North America or to reduce the risk of diffusion of other possible Pathogène S of game). However of many wounded animals flee and hide carefully to die. Their lead can poison the Charognard S, sometimes far from the place where they were wounded, or later. Lastly, of many vultures have an enough fine sense of smell to exhume insufficiently buried corpses (and to bury the remainders of corpses in the rocky places is difficult). Hunting for the arc which develops presents like means of driving out more “properly” from the " point of view; heavy metals " and in perturbing less the Environnement, but it is still practiced by only by one very small minority and requires more skill and precision that with the firearms. Moreover if it proved that the shot is one of the important origins of this lead poisoning, it will be Biodisponible decades and perhaps of the centuries in the environment.

Outlines

A project is to make isotopic analyzes lead to know for example if the shot or the balls is mainly responsible, or if there would be other sources of lead. This type of analysis allowed Canada and at the Inuit S to prove in an undeniable way the responsibility for the lead of hunting in the lead poisoning which assigns the Inuits babies whose parents consumed birds which them same introduced lead balls of hunting. This approach would make it possible to trace the origin of the lead measured in the blood of the Condors, and to identify the origins of them: drive out, fishing, natural geological bottom, lead remainders coming from the gasoline leaded (prohibited in the USA since more than 20 years) to reduce effectively, i.e. with the source, the intakes lead to the environment.

To increase the chances of survival of the species, in November 2002, the zoo of Los Angeles, after having tested new a Vaccine against the West Nile Virus on captive condors, decided to vaccinate the condors reintroduced in nature, in order to preserve them this disease which could be an additional factor of threat for this species always threatened of extinction. The virus of the fever of the Nile, probably imported Europe and diffused by the mosquitos kills many birds of the American zoos, in particular the tubes with russet-red tail and the owls large dukes of America who were decimated there.

Conclusion:

The data gathered thanks to these condors confirm if need be that the lead of hunting affects in a way serious and major species-key such as the vultures. They invite to a regulation imposing of the Munition S not poisons or less poisons (on shot, but also balls) or other modes of huntings (arc, trapping nonwounding and dead " propre"). The 17 Condors of Wilderness Society constituted in 2002 about half of the total population of the free wild condors of the world (40 birds at the end of 2002). All were high in captivity in Los Angeles and San Diego before several months of reacclimatation to the wild life (at the 6 months age) with the sanctuary of the Ventana Wilderness Society' S . At the end of 2002,202 individuals survived in the world, including 129 in the zoos in captivity. On 73 Condors reintroduced and surviving in nature at the end of 2002,40 lived in California, always vulnerable to lead poisoning even in the zones chosen for its reintroduction where the risk was considered to be the least low. This species can be regarded as a Bioindicateur of the state of the environment and secondary impacts of the lead of hunting. In other countries, close species, whose vultures in strong regression on almost all planet, would be also touched by this intoxication. This bird was saved because become a species headlight from its size and its notoriety. Elsewhere, 1.200 avian species are still threatened according to the UICN and could disappear in XXI^e century if nothing is done according to BirdLife International. The cartridges and balls without lead are one of the means of decreasing the risk, but the ammunition accumulated in the environment will remain a long time a source of intoxication of the birds and the their predatory ones, and can one think of the consumers of certain game.

See too

Notes/Sources

Source 2002) * article/the USA
Bibliography on avian lead poisoning

Internal bond

External bonds

ecotoxicology ecology

Random links: