THREATS
There are eight major threats to the condor. Each individual is very valuable for the long-term survival of the species. The individual gene pool helps the whole population. The knowledge of elder condors is invaluable for the younger ones. It is important not to lose a single individual.
1. TRASH
Condors feed on the flesh of decomposing animals. While they eat, they will swallow bits and pieces of the carcass bones, from which they obtain calcium and other essential minerals. These large scavengers are constantly looking for food from any possible source. In their search, they often find small pieces of plastic, metal, glass and other hard man-made objects, whether in human dumpsters or scattered around in nature. Unable to distinguish these hard objects from bone, the condors will swallow them, which eventually results in either illness or death. Moreover, condor parents feed their nestlings with food polluted with harmful pieces of micro-trash. As all other raptors, condors can regurgitate to get rid of unwanted objects they cannot digest, but in some cases, during breeding season, the amount of trash parents feed their chicks is so severe the birds that nestlings cannot regurgitate all objects. Provided this problem is detected in time by wildlife managers, the birds chicks have to undergo surgery to have all those unwanted objects removed from their bodies or else perish.
In the photograph below you can see a selection of trash collected from the pellets that condors regurgitated in the National Park of Sierra San Pedro Martyr. Objects ranging from bottle caps, small glass, balloons and aluminum foil to the ubiquitous plastic belts can be found in these remote areas.
2. LEAD POISONING
Since condors will eat any hard object found in a carcass, they often swallow lead ammunition from nearby game that was left in the bush by hunters. Not only is ammunition a problem; when a bullet hits an animal, it leaves retained bullet fragments composed of lead as the ammunition breaks up through the animal, which are in turn consumed by the birds. Lead is the mayor cause of death for populations of condors in the wild.
Non-lead Partnership Home | Non-lead Partnership (nonleadpartnership.org)
3. CHEMICALS AND OTHER POISONOUS SUBSTANCES
It is a well-known fact that DDT, a powerful insecticide used during the first half of the 20th century to control insect populations, destroyed many bird populations globally. Birds that prey on other animals were particularly vulnerable because DDT bioaccumulated all the way up in the food chain, acquiring the highest levels for the bodies of animals that birds of prey feed on. These birds were so affected by this poisonous substance that their egg shells thinned to the point of breakage, considerably hindering successful breeding. Herbicides and pesticides in agriculture present a major threat to wildlife, even in remote places like the Sierra San Pedro Martyr.
Literature:
Christopher W. Tubbs (2016) California condors and DDT: Examining the effects of endocrine disrupting chemicals in a critically endangered species, Endocrine Disruptors, 4:1, DOI: 10.1080/23273747.2016.1173766
DDT, the California Condor, and a Decades-Long Battle with a Banned Pesticide - One Green Planet
“Eggshell thinning is a phenomenon noted by scientists when studying birds exposed to DDT. As the birds’ natural ability to metabolize calcium is negatively impacted, the eggs they lay have very thin, weak shells. They cannot support the weight of adult birds sitting on the nest and simply crack before the baby bird inside has had a chance to mature into viable offspring. Problems with eggshell thinning as the result of DDT are well known in bald eagles and brown pelicans, as well as condors.”
4. POWER LINES
Electrocution is another major cause of bird deaths. When a bird makes contact with two different body parts on different wires, a high voltage runs through the bird’s body and immediately results in death. Ever since San Pedro Martyr National Park banned this kind of infrastructure the region has been protected, and there have not been any condor deaths in the park due to electrocution on power lines.
Small Shocks Help Enormous Birds Learn To Avoid Power Lines : NPR
5. WIND FARMS
Unfortunately, there is a wind farm very close to the San Pedro Martyr Sierra’s north edge. Birds cannot gauge the speed of the windmill’s blades, and many die in midflight when they collide with their trajectories. There is no record of the casualties of Baja California condors due to the impact of wind farms up to date.
Wind turbines are killing condors | Wind Energy News (wind-watch.org)
6. WILD FIRES
Coniferous forests evolved with fires. Some of the seeds found in this ecosystem need wildfires to germinate. Cold fires burn and clean the undergrowth, preventing warmer fires to build up and kill larger trees. When the fires are provoked by human activity in the middle of the dry season, however, the flames go out of control, bringing about severe losses to wildlife and the forest’s equilibrium.
Severe Wildfires Are Devastating the California Condor | WIRED
The California Condor: A Lesson in Wildfire Resilience | NEEF (neefusa.org)
Picture by: Felipe León
7. NATURAL PREDATORS
Sierra San Pedro Martyr National Park is a rich and diverse ecosystem that protects large predators like the mountain lion and the bob cat. Both felines have been caught praying on juvenile and unexperienced condors in this area through hidden cameras.
Picture by: Jaqueline Delgado
Picture by: Catalina Porras
Picture by: Mohamed Saad Luna.
8. AVIAN BIRD FLU´S
Bird flu viruses can infect the respiratory and gastrointestinal tract of birds and have been identified from more than 100 different species of wild birds around the world. Highly Pathogenic Avian Influenza (HPAI), sometimes referred to as the bird flu, is a highly transmissible disease that impacts birds, particularly waterfowl and poultry. Because many species of raptors and scavengers will feed on these types of birds. Even worse, raptors often do not show signs of the disease until they are on the brink of death—a common fate for infected birds.
9. DEFORESTATION
One of the possible reasons for the dramatic decline of the California condor population could be the fragmentation of its habitat. Condors are wild creatures that can adapt to certain human-caused disturbances, but when these actions diminish the natural food, they depend on, the condors have to migrate or perish. Deforestation, as shown in this photo taken at the San Pedro Martyr Sierra, is always adverse for biodiversity and for the condors.
