'The condor release sites are chosen for a variety of reasons," says the Wild Animal Park's curator of birds Michael Mace. "[We must get the birds] in a location that is very remote so they will not be around people, and we also have to take into account the ability to service that facility [local staff must be able to reach the site]. We look at wind direction and thermals -- the birds use those to fly around, so they can easily traverse the area -- and we make sure food sources are available." On Friday, April 28, Zoological Society of San Diego condor biologist and leader of the condor reintroduction team Mike Wallace will lecture on the California Condor Recovery Program as a guest of the Sierra Club's San Diego chapter.
The California condor's wingspan of up to ten feet makes it the largest flying bird in North America. The endangered birds reached their lowest point in 1982 when only 22 were accounted for in the world. Condors have few natural predators, and the bird's near extinction was the result of factors including pesticides like DDT (which thins the eggshells), collision with power lines, and poaching of eggs. In 1987, "A landmark decision was made to bring all the birds in from the wild to two facilities -- the San Diego Wild Animal Park and the Los Angeles Zoo," says Mace. "Since that time [our facility has] produced 128 chicks, and there are now over 270 condors in the world."
Four breeding facilities yield around 30 chicks a year. In the wild, a pair of condors produces one chick every two years. With the use of "puppet rearing," condor biologists are able to double the number of offspring in captivity. When a condor couple produces an egg, scientists remove that egg and put it in an incubator. The condors then produce a second "replacement egg." When the egg in the incubator hatches, it is raised with the use of a puppet made to resemble a mature condor. "This way," says Mace, "the birds never see people, they just see the puppet, so they know they are a condor during their impressionable period."
Both at the hatching facilities and at the release sites, "mentors" (adult condors that behave as a condor should) are used to teach chicks how to survive on their own. "Youngsters are integrated with mentors and start to learn skills. They watch the adult bird forage for food and watch how the adult behaves." A chick may stay in the aviary with a mentor from one month to six months. The aviaries at the release sites allow chicks to grow accustomed to the climate. Also, "The mentor stays back [in the aviary] and serves as a beacon for chicks to know where they can come back to so they don't get too far off on their own and get into some kind of trouble, like getting lost."
The two primary release sites in California are located in Ventura County and Big Sur. The San Diego facility's release site is located 7000 feet up in the San Pedro de Mártir Mountains in Baja California, a seven-hour drive from the border. It takes three to four hours to reach the site by car from the nearest town. "As a condor flies, that's not a long distance," says Mace. "In Arizona the birds travel more than 200 miles a day." A total of 16 condors have been released at the Baja site over the past four years.
"Since its inception, going back to the early '80s, the entire project has [cost] somewhere around the 20- and 30-million-dollar range," says Mace. Including all departments (e.g., research division, behavioral division, pathology department), San Diego's facility requires "around a quarter of a million dollars a year." This money comes from ticket sales to the San Diego Wild Animal Park and Zoo and donations.
Released condors have been reproducing on their own, hatching and raising approximately five chicks a year between California and Arizona. "That number will grow exponentially as [the birds] mature." Chicks do not reach sexual maturity for at least 5 years, but their lifespan is 60 years. Condors are social animals; outside of the breeding season, which is the first half of the year, they congregate in larger numbers (eggs are usually produced in January, take almost two months to hatch, and at least another five months before the chick will leave the nest).
"In general, condors are an incredibly hardy species," Mace points out. "They live a very long time," and their strong immune system keeps them from becoming sick from bacteria found in the rotting carcasses on which they feed. "But with that said, they're also very vulnerable to the environmental issues that affect all of us. We're not saying not to develop, just [that people should] take into account all of the things that [can be done] to be responsible in a community. Using California as an example, if you just preserve and manage effectively the property that condors live on, there are fifty other endangered species [living there] -- they may not be as well known or charismatic, but if you take care of the one you know about, there are plants, reptiles, other birds, and more that will benefit as well." -- Barbarella
Bi-National California Condor Reintroduction Program
Lecture by Michael Wallace, Ph.D., Zoological Society of San Diego condor biologist
Friday, April 28
Joyce Beers Center
3900 Vermont Street (in the Ralphs/Trader Joe's shopping center)
Info: 619-299-1743 or www.sandiego.sierraclub.org