April 2007
Eddie Feltes— 3 May 2007 — in California Condor Restoration    ShareGreetings NFTF readers, April 2007 has had our field crew working hard tracking condors as they start to actuate into their summer foraging patterns. We can always bet that come April/May the flock will start to expand in both range of flight, as well as time spent away from the release site. This change in seasonal movement is attributed to the increasing temperature that allows for more efficient soaring conditions, and the return of the condor’s most useful ally in locating carcasses to feed upon- the turkey vulture.

The month of April had our crew documenting several non-proffered carcasses known to have been fed upon by condors; including elk, mule deer, and bison. It has been a constant trend with the Arizona population to step-up foraging success, once all the turkey vultures have migrated back into northern-Arizona and southern-Utah.

As many of you already know, the Zion region of southern Utah has become a favorite seasonal residence for a large portion of the condor population. And in the past few weeks, we have already documented birds making the approximately 150 mile round-trip flight. On 18 April, Condors 266, 343, and 352 all made the trip, and stayed for a few days before returning back to the Vermilion Cliffs of Arizona. And on 28 April, 14 condors, all birds that have spent time there in the past, made the trip and are all still remaining at the time of this writing. The region is perfectly suited to meet the needs of a wild condor population—large herds of ungulate species providing carcasses to feed on, diverse topographic features allowing for optimal travel/foraging, and a network of deep canyons that contain great nesting and roosting sites.

With all the seasonal movement at this time of year, the duties of the field crew monitoring and observing must be spread thin. We start to really focus on the most traveled and aggressive foragers during this period, and five-year-old Condor 270 is a prime example. Being a fairly predictable bird over the past few months, I felt it was odd that we had not had contact with him, via transmitter signal or visually, for a period of five days. He was not traveling with the same group of birds that had been frequenting the Colorado River corridor. So we stepped up tracking efforts in search of our missing bird. Not until going eight days without contact, did we receive movement on his signal from the south rim of Grand Canyon National Park. A huge sigh of relief set in, but we still like to get visual confirmation to assess any possible health concerns or injuries that may have led to the sudden change in pattern. Two days later we received Condor 270’s signal back at the release site, making us modify our plans from observing a nearby active nest cave to heading up to the blind to get some eyes on him the following morning. While watching and recording feeding data from the observation blind, veteran crewmember Eric Weiss noticed Condor 270 behaving oddly. He was grounded below a proffered carcass location with a considerable limp as he favored one of his legs, and several ravens had already taken note and began harassing the injured condor. Realizing the seriousness of the situation, Eric and I quickly developed a plan to trap him and seek out medical attention. Once trapped and in hand, we were able to confirm that Condor 270 was showing no functionality with the injured leg, and decided to transport the injured bird to the Phoenix Zoo and the care of Dr. Kathy Orr. Once examined, Dr. Orr confirmed a fracture in the tibiotarsus bone of the right leg. At the time of writing, Condor 270 is healing as expected for an injury such as this, and our hopes are high for re-release back into the wild.

In last month’s NFTF, I avowed my expectations of having a few more condor pairs attempting to nest this breeding season. Based on close observation of behavior and daily movement pattern, it appears Condors 126 and 114 and Condors 253 and 223 have begun incubation in remote nest caves. Recall that Condors 126 and 114 successfully fledged Condor 389 back in November 2005, thus fueling our confidence in the pair pulling off another fledgling based on experience. And Condors 253 and 223 are a new pair that is showing a nesting attempt for the first time this year. Again, these are only suppositions based on data collection and close observation of nesting behavior over years past. Of the six eggs believed to have been laid so far this year, we have only had visual confirmation on one, due to the lack of clear sight into the other nest caves.

We would like to honor the hard work and dedication of crew member Frank Nebenburgh over the past three years. Frank has moved on to a new career in Ecuador, and his passion for condors and joyous personality will be missed. Thank you Frank, and good luck!

Find more articles about California Condor, North America