It wasn’t long before we realized that #261 not only maintained his flying superiority over all the other condors but, with his beak healed, he was steadily climbing the social status ladder. He could easily out fly and harass the other birds in flight and somehow that flying edge seemed to translate to dominance at the carcass as well. It all seems logical now that a social flying species would spend a good portion of their airtime in dominance interactions. Perhaps condor challenge bouts in the air are equal to or even more important a mechanism for status determination than interactions we can document on the ground around a food or perch resource.

As #261 gained dominance over the 3 older females our observations of their “affiliative” interactions (who likes to be close to whom) indicated that a relationship was building between him and the previously alpha bird in the group, female #218. They could be seen feeding more closely with more tolerance than one would expect, teaming up aggressively on others and “allorubing”; making contact with the bare skin of their necks in an affiliative way. Although breeding age of 5 to six years old was still a few years away, we wondered if we were witnessing insipient pair bonding that would eventually culminate in territorial defense and a nesting attempt.

Just as this hierarchal pattern appeared to stabilize with #261 and #218 as a likely pair at the top, we documented a rapid shift. Four birds, including the “pair” made a several day excursion to the south but only three returned. A day later #218 finally made it back but was obviously limping with a swollen left foot. The ailment eventually healed on its own over a two-month period but not without noticed by her challengers, # 220 and #217. Taking advantage of #218’s compromised physical condition, #220 was able to quickly establish herself as the most dominant female of the group. It was clear that #218 had lost favor with the dominant male #261 as they spent less and less time together. We noticed within two months, however, that #220, now the reigning dominant female was taking long flights together with #261 and soon they could be seen feeding with lowered aggressive interaction and deference between them at the carcass. She now appeared to be the favored one and made that clear to the other more subordinate females. What will happen next as #220 reaches breeding age? Check back with us to find out.

Chick No. 450 was temporarily removed from her nest for surgery related to trash. A physical exam of chick 450 at 91 days of age showed poor tail feather growth and labored and rapid respirations. We also observed a decline in activity levels prior to this entry. At 94 days old she was removed from her nest and transported to the Los Angeles Zoo by helicopter where Dr. Wynne performed surgery on the chick, removing an impaction of trash items and hair form her ventriculous. She was also diagnosed with bacterial pneumonia and treated with antibiotics before being returned to the nest 23 hours after her removal. An additional entry followed up this treatment a week later so that antibiotics could again be administered and the surgery’s suture could be checked. Observers tracked her recovery as activity levels increased and following exams showed resumed feather growth. All other entries were conducted without event with the help of the L.A. Zoo condor keepers and veterinary staff, who deserve our thanks for enduring the long and steep bushwhacks and climbs in the brutal heat of the summer months.

All chicks in Southern California had their wings fitted with VHF transmitters and tags at about 100 days of age. The decision to place patagial-mounted transmitters on chicks was not without concern as there have been some physical problems recently with wing-mounted transmitters on free flying birds. In the event of a transmitter malfunctioning or riding improperly, it would be sometime before chicks could be trapped at feeding sites for replacement or repairs increasing the chances of wing damage. These concerns were weighed against the increased ability to gather data on naturally fledging chicks, something that has not been accomplished in the past, and in the event of a problem provide the ability to intervene on the newly fledged chick’s behalf. Thus far, the transmitters have been extremely valuable in both tracking the active chicks progress as they move away from the nests to more remote locations and during the Ranch Fire. The location of condor 443 post mortem was also determined via radio telemetry. The transmitter of No. 450 has been observed in a flipped position and there is concern to the way that it is riding. This may have been due to the small cavity size of this chick’s nest where the chick may have caught its transmitter on the cavity walls while wing flapping. All other transmitters are riding without observable reason for concern. In 2008, we will be looking closely at new transmitter attachments for chicks.

Fledging came at a variety of ages for these chicks. The youngest being No. 443 took flight from the nest cliff after being harassed by an adult female from the population at 142 days old. Despite the continual harassment by this adult female, chick. 443 continued taking short flights down low in the canyon and quickly learned of other threats from terrestrial predators (black bear and bobcat) that were observed in the vicinity of her location in the lower canyon region. Regrettably, at 23 days later this chick was discovered deceased at a location about 500 meters from where she was last observed. The direct cause of her death has not yet been determined but it is likely to due to post complications following the Ranch fire, which burned through the area and the Hopper Mountain National Wildlife Refuge in late October.

The oldest chick, No. 428, fledged at 155 days of age when she was observed taking short flights to a more removed portion of the nest cliff. Her progress has been tracked closely over the last few months and has been observed several times flying over and feeding at Hopper Mountain with her parents (about six miles from her nest site). We have been relying primarily on radio telemetry and the occasional visual to track her progress as she continues to integrate with the rest of the free flying population.

Condor 450 fledged at 179 days old on Nov. 10 – a true sign of her recovery from surgery She still remains within the nest canyon but has began roosting with her parents in a snag about 50 meters from the nest cavity. Her location makes this chick the easiest of the fledglings to observe allowing us to closely follow her interactions with her parents.

The final chick to fledge did so at 208 days of age. Chick 449 has been taking short flights and spending time on the cliff faces immediately across the canyon from the nest site. This chick seems to have of a delayed age of fledging relative to the rest of this season’s chicks. A possible explanation for this could be related to the topography in the immediate vicinity of her nest site, which is much less vertical and allows her to venture out distances of about 60 meters without taking flight. Two of the newly fledged chicks, 428 and 450, have also been observed interacting with golden eagles. In these cases the eagle has aggressively swooped down on the chicks often making contact and grounding the chicks around their nest cliffs. We have not observed any injury as a result of this aggression but this certainly could be a threat. If the parents are in the vicinity they defend the chicks by chasing the eagles away.

The treatment consists of daily administration of two doses (one injection and one oral) of calcium EDTA that binds to the lead in the blood and flushes it out through the kidneys. Baring complications, high lead levels in blood can be reduced to near background levels within a few weeks, and in most cases, birds can be released back to the wild.

Heavy sleet/rain (over 4 inches) and winds (over 60 kts) made trapping some of the condors in Baja challenging. Field assistants Juan and Catalina did an incredible job during this event. However, field conditions and a recent drop in field staff made it impossible to efficiently and safely treat the birds in Baja.

With trapping ongoing, we tested 12 additional condors for lead on Sunday, November 25th. Five more proved positive and were relocated to the Wild Animal Park on November 26th for chelation treatment. Days later, the last two birds were tested. One proved positive and was also transported north. Of the 22 birds in Baja, all were tested; 11 were positive and in need of treatment. All birds were radiographed on arrival at the hospital and only one, #323, retained a single shotgun pellet in his gut. Attempts to retrieve it by flushing the GI tract and using a laparoscope have been, so far, unsuccessful but efforts will continue.

Condors are very hardy birds. To give some perspective, bald eagles that Dr. Pat Redig at the Raptor Center at the University of Minnesota treats for lead toxicity often die at lead contamination values just over 100 ug/dl. During the course of treating these condors, a more refined analysis of blood lead levels from an outside lab indicated that lead values in all birds were well over the 65 ug/dl (as indicated by the field lead test kit) and some values as high as 590, 600 and 640 ug/dl. Unfortunately, condor #325 died suddenly while the group was being treated. We are not sure whether it was related to the lead intoxication, the treatment, or a combination of these and other unknown factors. Of the many dozens of condors treated in this way, only two other condors have died under similar circumstances.

Since both free flying and pre-release captive birds were affected during the recent episode, it is likely that the lead was in food that we fed to both the captive and free flying groups. We buy live and dead large domestic animals from local ranchers and have to rely on the owners, when possible, for their health history and our site manager Juan’s inspection of the carcass. After the lead poisoning case in Baja of captive bird 319 in 2005, we have been scanning with a metal detector each carcass (horse, cow, or goat) for lead from potential gunshot wounds acquired earlier in the animal’s life. This technique works, but unfortunately it is only effective to a few inches in depth, which apparently still leaves sufficient risk that lead shot deeper in the tissue can go undetected.

To reduce the risk of lead contamination in the future, we acquired field, digital x-ray equipment so each carcass proffered to condors in Baja can be entirely scanned for lead prior to being fed to the birds. While cumbersome, this technique should drastically reduce the risk of future lead contamination exposure.

As reported by Wild Animal Park veterinarian Dr. Jeff Zuba, all our condors were off treatment (lead levels less than 30 ug/dl) by January 10, 2008. (Treatment lasted 1.5 to 6 weeks, depending on the contamination level of the bird.) How quickly we can get the affected condors back into the field will determine the overall negative impact to the program. With the exception of a few glitches, all agencies contacted on both sides of the border have been immensely helpful to this point. CITES permits to re-export the birds have been applied for out of Dave Rimlinger’s office at the San Diego Zoo.

Again, I would like to thank all those involved with this operation including the Baja condor field staff, the keeper, vet-tech and vet staff at the Wild Animal Park. Mike Clark for coming from LAZ to assist in training the hospital keeper staff. USDA, PROFEPA and USFWS have been exceedingly corporative and helpful during the transfers with Dr. Fernando Sanchez coordinating the many details on the Mexico side. Dr. Jeff Zuba supervised many transfer details and coordinating the hospital treatment. The keeper staff at the hospital did an amazing job of managing the eleven condors considering safety, behavioral isolation and USDA quarantine. Only after re-release to the wild will we be able to determined the behavioral effect this experience has had on the birds.

It was a productive year for California. The breeding effort for the season was 36 percent out of 21 adults that are six years of age or older. Southern California had eight pairings involved in courtship behavior at the start of the 2007 season. Four of these pairs produced nests. One pair that did not nest had attempted to nest the year prior, condors No. 98 and No. 112. It is unknown why this pair failed to produce an egg though it might relate to the previous mate, condor 216, competing for the male’s attention. A second pair that was observed in courtship that failed to nest was condors 237 and 214 that were successful in 2006. A combination of lead treatment and post fledgling care likely prevented their 2007 attempt. The final two non-nesting pairs both involved males that just turned six years old this season. In 2007, one of the four pairs to nest was a first time pairing, condors 206 and 255. No. 125 and No. 111 were involved in their fourth nesting attempt in the wild, returning from their period at the San Diego Zoo’s Wild Animal Park where they produced condor 417. Condor No. 21 (AC9) and No. 192 also made their fourth attempt this year. Condor 107 and 161 nested for the third time.

Egg fertility was 75 percent. The egg laid by No. 111 was infertile. Transplanting a viable egg from the Wild Animal Park prevented nest failure. The nest history for condors 21 and 192 indicated questionable egg viability with only 33 percent hatching success. We therefore preemptively transplanted this pair’s egg as a means to determine egg health. The first egg used to substitute the dummy egg that this pair incubated failed to hatch due to malposition. The pair’s original egg was then used as the second replacement egg, which hatched successfully. During the egg stage, there were seven entries performed on the nests. One was for a fertility check of the first time pair’s egg and all others were while performing aforementioned egg transplants. Only a single micro-trash item was recovered from the five nests that were entered during the egg stage. One nest (condors 107 and 161) was not entered during the egg stage because of the 100 percent hatching success observed during their previous two attempts.

Joseph Brandt will continue this story with specific information on how each chick hatched in 2007 faired in part two of this blog. Stay tuned for 2007 California Condor Breeding Season - The Chick Phase

The many hours of observation contributed toward behavioral data that have been used to enlighten concerns such as egg failure, extra pair interference, eagle aggression and trash ingestion. These observations identified points in time where it was necessary to make interventions on behalf of the wellbeing of a chick or egg. Members of volunteer clean up parties enacted an offensive against trash being brought to nests by cleaning up known problem areas that our pairs have frequented. For this, we extend our thanks.

The US Fish & Wildlife Service would also like to acknowledge and give many thanks to all of our partners who have helped make this season a success. The Santa Barbara Zoo (specifically Alan Varsik, Estelle Sandhaus and Shaun Putz, who is now with Peregrine Fund) has been a strong new partner in the field as co-creators of this season’s nest guarding program, providing assistance in nest entries, nest observation, volunteer recruitment, volunteer training and data entry. They also provided a contingency fund for helicopter operations in California.

The Los Angeles Zoo played an integral role in providing handler and veterinary support for nest entries and providing many opportunities to help teach the techniques involved in handling condor eggs and chicks of a variety of ages. In turn, the Pinnacles National Monument provided the opportunity for many of those involved with nest entries to receive training and experience working on high angle terrain. These training opportunities translated into not having a single injury to staff or birds during nest entries this season.

The San Diego Zoo’s Wild Animal Park also provided support with a captive laid egg that is now a fledged chick, increasing our success this season by 25 percent, necropsy support for condor 443, as well as assistance from Dr. Mike Wallace in training and support with tagging and placement of transmitters on the chicks. Finally, Ventura County Search and Rescue provided helicopter support early on in the season during egg transplants. An 11-month season has meant a huge commitment of time and energy from volunteer observers to staff from partner agencies! We are extremely grateful for all the help and assistance. We look forward to future nesting seasons as we make real progress towards creation of a self-sustaining wild population.

Condor #261 is at the top of his game. The alpha male presiding over a small but growing group of 16 birds in the Sierra San Pedro Martir of Baja California, he enjoys his pick of perches, deference by others at the feeding sites and, apparently, his choice of mate. It was not always so easy for #261, in fact, he started at the bottom of the pecking order when he and 4 other condors, a male #259 and three females, older by one year, arrived at the release site in August 2002. He had been somewhere in the middle of the group in status, but when he was captured from a large aviary on transport day at the Los Angles Zoo’s condor breeding facility, he incurred an injury to his beak that left him in some degree of pain as he healed over the next few months. Conferring with the zoo’s veterinarian, we decided that the non-life threatening broken beak tip would heal on it’s own and he could retain his ticket on the small plane to Mexico.

Since a condor’s beak is the primary weapon of defense from other attacking condors he was automatically relegated to the bottom of the hierarchy when the 5 birds were placed in the large release site aviary. For over 2 months he could be seen feeding off to the side of the group or when the others were absent around the carcass. Any encounters with the others often involved submissive wing-begging displays that kept him under the radar of the more aggressive encounters of the other birds as they ironed out their social differences.

To test how the first releases would go in the new area, three of the five birds would be released first. When the 20’ by 20’ by 10’ high pen, attached to the larger 60’by 60’ by 30’ aviary door was opened to capture the first release candidates, #261 was, by chance within the first group. Since we didn’t know if his low status would have any relevance to when he was released or which group he was released in, he was released with female #18 and Male 58, the two top ranking birds in the group. Remaining behind in the flight pen were #220, the female next in status and the shy female #217 who stayed in the back ground and would have been at the bottom of the hierarchy of the group if it wasn’t for #261’s beak injury.

Our first release turned out to be a near disaster. Golden eagles, a species known to kill condors on occasion, drove both #218 and #259 to the ground with a series of unfriendly strikes, causing the female to remain in the bushes over night and the male to head south. I spent the night with the downed bird and at dawn she had climbed into a small tree seemed fine but headed south low along the ridgeline as well. Neither of the attacked birds would attempt to gain altitude in thermals presumably in fear of further interactions with eagles. Without altitude they could not get the lay of the land so could not orient back to the release pen.

Over the next two weeks they both wandered south separately without food or water. Typically released condors hang close to the release point orienting on the other condors and locking in on the food and water placed out on the release area. Eventually they both had to be trapped back into captivity, one in the chaparral at 3:00 AM about 17 miles to the south and the second that flew nearly as far in another direction and had to be grabbed 50 feet up in a pine tree after dark. Meanwhile our subordinate condor, #261 did exceptionally well. He somehow escaped the wrath of eagles, learned to soar and successfully oriented back to the release pen. Not wanting to have a single condor free through the winter we trapped him and placed him in with the other condors but by then he had learned the area and was flying quite well. Stay tuned for the next installment that looks at springtime releases and the adventures of #261!

• Note taking technique and observation protocol.
• Ethogram and behavior identification.

Volunteers who are interested in becoming a California condor nest monitor are required to attend one of these trainings. 2007 monitors who wish to continue into the 2008 season are also required to attend one of these trainings.

More about the project:
In addition to completing training in our monitoring and data collection protocols, nest monitors will spend long hours in the field in inclement conditions and, depending on nest site location, may be required to hike and camp in the backcountry. Monitors will be required to use their own vehicle for travel to, from, and in the field. Volunteers are sought who can commit to regular observation days (minimum two/month) over the full breeding season of six to eight months.

At every stage of the condor conservation management and reintroduction program, great care is taken to prevent condors from associating humans with food. Otherwise, the insatiable curiosity of these birds will inevitably lead them into trouble and into garbage dumpsters and alleyways looking for an easy meal. Hence, we get up unseen under the cover of darkness to shift the carcasses that we have sourced the day before to an escarpment where we know the condors can later “find” a recently dead animal for brunch.

I am in this blind with the carcass outside waiting for the condors to arrive so that I can ground-truth the location data we receive from the GPS-tags attached to the birds wings and analyze the dominance hierarchy (or pecking order) of their social structure. That way we will be able to interpret the birds spatial patterns and habitat use within the context of the lurid soap opera that is the condor’s social system.

One-way glass in the walls of the blind lets me peer out into the condor’s world without them analyzing me back. With a few more hours to go before it is anticipated that the birds will start arriving to check out the meal we have left for them, I check that my camera, binoculars, and field gear are all in order then settle down to snatch a few moments of snooze as the sun begins to splash over the horizon.

Was that the rustling of an animal outside or just my imagination playing sleepy tricks? No, that’s definitely something moving. Or, should I say something munching? Far too early for a condor! I creep over to the view port to check out the carcass. Not a condor, a bobcat (top photo). A very appealing critter but an unwanted guest at our condor “restaurant”; we’re here to feed the critically endangered birds, after all. Bobcats are extremely cautious and wary animals but their presence at a carcass will deter any condor from coming down to feed. Indeed, a bobcat will have a go at a condor if given the opportunity and one of our birds is sans a few tail feathers from just such an encounter.

I open the door to the blind to quickly scare the bobcat off the carcass before I’m spotted by the condors, but with a flash it is gone before I can even say,
“Boo!” Back inside. Back to snoozing. Less than an hour later: same munching noise from outside. Back outside to scare off the same bobcat. And yet again, half an hour later. The third time scaring the bobcat was the trick and it didn’t reappear. Unfortunately, a couple of coyotes then decided to check out the tantalizing odors wafting from our goaty condor treat. Unlike the bobcat, the coyotes couldn’t get through the fence surrounding our condor compound and onto the carcass. However, their presence would be more than enough to scare off the birds. This morning, will the birds stop by to feed and will I have the chance to observe their behavior? More to come on the adventures in the blind!

What continues my 30-year fascination with this highly endangered species is its intelligence and social behavior. Like primates or social carnivores, each bird has a specific ranking within the pecking order of the local population. This social status is based on age, experience, sex and physical attributes like weight and physical ability. Condors are all about conserving energy and an ordered social hierarchy reduces the amount of time individuals spend in altercations over resources. While continuous, mild, non-violent displacements occur throughout the day by dominant birds towards subordinates over resources such as food, perches and even air space, higher intensity aggression is usually seen only between two birds of nearly the same rank. Since every two to four days the birds return to the feeding sites, we can tally the winners and losers of their interactions and assess their hierarchal relationships from camouflaged blinds as they feed. By better understanding the social rules under which this gregarious species functions we gain predictability and can fine tune our captive rearing conditions and management for better behavioral results, and hopefully survivorship in released condors.

During our efforts to re-establish captive bred condors in Baja California, Mexico, that we have been conducting since 2002, I have had a chance to get a closer look at these social workings. What determines a bird’s status in the first place involves the parameters mentioned above, yet an individual’s social position is not cast in stone. So a big question is what are the social rules and environmental conditions that allow a bird to increase (or decrease) its social status?

To establish a condor population in an area they once inhabited we, in effect, train them to a site with behavioral management, food and topographic features that will enhance their ability to become competent flyers and learn how to function as condors in their new “wild” environment. Since they are completely dependent on us for food and water, as they would be with their parents for an extended period of months after fledging, we provide large animal carcasses in and immediately outside the release pen where they can watch the smaller scavengers and previously released condors feed.

Condors rely heavily on each other, particularly more experienced birds to consistently find food. Not having the olfactory ability of the smaller turkey vulture, condors use observation of the activities and behavior of the more numerous smaller scavengers as well as other condors to find a carcass. Historically they also had the benefit of learning the tried and true foraging traditions that developed over centuries in their local population that would indicate where food was likely to show up in any given period of the year within their potential foraging distance of several hundred miles. As expected, it is taking decades for our released condors to develop a functional food finding tradition in areas we are attempting to re-establish them. To manage the process we subsidize the inexperienced population with carrion proffered at various times and locations in their environment thus encouraging natural foraging.

Condors are scavengers and range widely in search of food. The carcasses on which condors feed are spread around a large habitat and are extremely variable in abundance and distribution. Hence, understanding how condors forage effectively in the wild is crucial to their conservation. Condors also require consistent thermal air currents to conduct long-range foraging movements. A central hypothesis of my study is that the environmental factors specific to condor habitats shape their movement patterns and habitat use.

Condors also have complex social dynamics and form dominance hierarchies (or “pecking orders”). My project will determine the role that social relationships play in condor foraging and habitat use. Studying the interaction between condors and their habitat requires knowledge of their movement patterns at scales relevant to both condors and managers. This has not been possible in the past because of the difficulties of direct observation of condors and the low resolution of tracking equipment. My project capitalizes on incorporating accurate GPS technology into tracking equipment to monitor the movement patterns of wild condors at very high resolution for extended periods (years). Better understanding of condor spatial ecology will provide the ability to model and map condor habitat use and foraging patterns at scales that are suitable for informing policy of condor reintroduction programs and the management of human sources of threat to condor populations.