Winged visitors alien to the area have been casting their large shadows over Contra Costa and Stanislaus counties recently. Preservation group Save Mount Diablo said in a statement Monday they’ve tracked the paths of six California condors soaring through the skies above Round Valley and Morgan Territory regional preserves, with one even flying a mile or two west of Mount Diablo’s summit.
“This is amazing news,” said Seth Adams, Save Mount Diablo’s land conservation director. “This is the first flock of California condors to visit Contra Costa in 100 years, and the first record of one flying west of Diablo’s peaks.”
Adams said he’s been “chasing condors” for 40 years, since the recovery program began. In the 1970s, biologists found only a few dozen condors remained in the wild, thanks to human activity. Lead poisoning in dead animals shot with human-made bullets has been a major factor in the condors’ decline. Condors are scavengers and may accidentally ingest lead bullets in carrion.
A major conservation project was started to save the California condor from extinction in 1980. According to the California Department of Fish and Wildlife website, wild eggs were collected and hatched at the Los Angeles Zoo and San Diego Wild Animal Park to help increase the population. A few condors were taken to the zoos for captive breeding.
But the efforts didn’t stop the decline in the wild bird population, so the strategy turned to capturing the rest of the wild population. The population was down to 22 birds at one point. The last wild condor was captured in 1987.
Captive breeding worked and the program began releasing condors back to the wild in 1992, mostly in the state’s central and southern coastal areas. The population grew from 27 birds in 1987 to 446 by 2016.

“I’ve been hoping the birds would reclaim Mount Diablo,” Adams said, “Now they are. This kind of good news is happening again and again. But what it really highlights is the importance of the giant Diablo Range as habitat for the birds — 200 miles north-south and 3.5 million acres of high-quality intact habitat.”
Save Mount Diablo said in recent years condors have explored the northern Diablo Range, lengthening their flights northward as they fly closer and closer to Mount Diablo.
