Meet 317 and 318, a young couple in California's Pinnacles National Monument. They are two of only 91 California condors flying free in the state – and only 349 left on Earth. This spring, the birds had no sooner laid an egg in their nest than National Park Service biologist Gavin Emmons rappelled down and swapped it out for a plastic dummy – and then, in March, replaced the dummy with an egg laid in captivity.
The egg snatching is part of a study checking wild eggs for harmful chemicals like the DDT derivative DDE. Swapping also increases chances for a successful hatch; wild eggs are sometimes nonviable (as this one was), and biologists can ensure captive eggs are alive before placing them in the nest. It's the latest phase in a recovery program begun in the mid-'80s, when the condor population dwindled to 22.
The new parents didn't seem to mind. On March 24, the changeling hatched -- the first California condor chick born in Pinnacles in a century.