For the springtime release a few months later it made sense to include our best flyer who had already proven his ability to orient well in the neighborhood. Still at the bottom of the hierarchy, #261 was released with the two other condors, #220 and #217, neither of whom had any previous negative experience with eagles. This release went exceptionally well with no eagle issues and within a month we released the other two condors to join the group. We later realized that territorial red-tailed hawks and ravens keep eagles out of the release area during their hatching and chick rearing season so spring and summer has become the best period to release condors, allowing them to learn to fly more confidently and lessening the severity of eagle attacks seen later in the year.

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.

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