With enough rope to make the 550-foot (170-meter) rappel to the cliff base, Juan Vargas and I moved steadily downward to this year’s only condor nest in the Baja California, Mexico, California condor release program (see post, Condors: Quest for the Egg). Situated in a 6-foot (1.8-meter)-deep cave punched into a massive granite wall, it was the same cavity this pair attempted to nest in last year but failed in the egg stage of incubation. This season they incubated an egg successfully, and the cave now housed a startled, month-and-a-half-old chick that began hissing and lunging at us as we landed at the cave opening.
From a settled sitting position in the cave entrance, I scooped the chick into my lap during one of its attacks to examine its crop for signs of microtrash ingestion, a problem seen in some of our wild condor chicks in the U.S. I palpated one hard lump up to its mouth and could see that it was bone and a healthy part of its diet.
Besides checking for general health and feather growth, we were there to administer a one-time dose of vaccine to protect the chick against West Nile virus. An experimental DNA vaccine developed by the CDC (Centers for Disease Control and Prevention) specifically for condors, it has proven 100-percent effective in guarding our captive and wild birds against the virus. One dose usually protects the condor for life.
We check the blood some time later and can administer another dose, but usually it is not needed. Kiliwa, as we are calling him/her after the Native American tribe in the northern Baja California area, is one of 15 condor chicks sitting in nest caves throughout the range where condors have been introduced in California, Arizona, and Mexico. Including all zoo production, an amazing total of 49 condor chicks have hatched this year!
Mike Wallace is a conservation program manager for the San Diego Zoo’s Institute for Conservation Research.