After nearly three years of placing uncontaminated food for California condors at Big Creek Reserve, biologists from the Ventana Wildlife Society (VWS) have confirmed that our local pair have finally built a nest here. Male 168 and Female 208 prefer to feed at Big Creek and are commonly sighted on the motion-detection camera. These are the parents of “Centennia,” the first condor chick successfully hatched in the wild in Monterey County in more than 100 years. Centennia was hatched in a cliff nest deep in the Ventana Wilderness in April 2007 and fledged in September only to disappear in early December, having last seen being harassed by an aggressive golden eagle. The parents took a year off and now have decided to try raising their young at Big Creek Reserve. Using a combination of GPS tag data and radio transmitters, VWS trackers identified suspiciously “broody” activity occurring on the Reserve. VWS biologist Mike Tyner quickly tracked down the site and verified one of the adults sitting on top of a hollow-topped redwood snag.
As luck would have it, the captive breeding program at the Los Angeles Zoo had an egg ready to hatch. Because Big Sur condors are still highly effected by DDT in the marine food web (they feed largely on sea lions that bio-accumulate DDT from historical incidences of dumping), biologists from VWS and National Fish & Wildlife try to swap healthy, captive-bred eggs for the wild eggs to encourage a successful brooding and fledging experience for the parents. Eggs laid by DDT-effected adults have thin shells that don’t properly hold moisture, resulting in dessication of the embryo. Within days a team was assembled and the captive egg was driven up from LA Zoo to make the swap at Big Creek.
Our group, consisting of Pinnacles National Monument, VWS and U.S. Fish and Wildlife biologists, hiked… no scrambled through heavy brush and poison oak to the nest site. USF&W egg delivery man and tree climber, Joseph Brandt, ascended the living tree next to the dead snag and found that the pair had indeed laid their own egg (which we later verified was fertilized). The small cavity was just big enough for the male to sit on the egg with his tail feathers hanging over the edge of the tree trunk. He sat in an adjacent redwood and flew back and forth, eagerly waiting to get back to the nest. Joseph made the swap with 168 watching over his shoulder.
As soon as Joseph rappelled back down the tree, 168 headed back to the nest. The condor pair’s egg was immediately driven back to LA zoo where it will be inspected for shell and membrane defects. It will be incubated for eventual hatching and release of the chick into the wild. I will be curious to hear about the condition of this egg’s shell. The level of DDT poisoning it has will shed light on how much this pair is feeding from the marine environment vs. the clean food placed on the Reserve.
Everyone was elated at this discovery and relieved that the nest is located on Big Creek Reserve. “We are so glad the condors chose Big Creek because we know their nest will be highly protected and we can work closely with the staff here. This pair has been consistently feeding at the Reserve and now we are seeing a fantastic result”, said Senior VWS Wildlife Biologist Joe Burnett. The mission of the UCSC Big Creek Reserve is to preserve its 4200 acres of wilderness for the purposes of research and education and we will be working with VWS to broaden awareness of condor research through our means of outreach. We’re all very happy that this collaboration has resulted in our local pair choosing a nest site at Big Creek Reserve. With a chick that is busting out of it’s shell they should be quite busy within a couple of days. Good luck to them!
Stay tuned for the video!
Keep track of this story on this blog and at www.ventanaws.org.
You can see pictures of 168 and 208 from the Big Creek feeding site.
Mark