Thom Lord— 2 August 2005 — in California Condor Restoration ShareGreetings, Notes from the Field readers! In May’s installment of NFTF, I mentioned that the month of June would be very telling in whether our three wild nests in Arizona had produced chicks or not. This certainly turned out to be the case, as the status of all three nests became apparent fairly early in the month. There was no evidence of anything amiss in the first couple of days in June, and all three pairs continued to exhibit normal nesting behavior. On 3 June, however, first-time breeders Condors 136 and 187 returned to the release site together and roosted there that night. This was not good news for their breeding attempt. Their chick, if they had one, would probably not yet have been old enough to regulate its own body temperature for such an extended period of time. We maintained some hope when the female returned to the nest cave the next day, but both birds were away from the nest and back at the release site two days later. Any lingering doubts about the nest’s status were removed when the pair remained away for two consecutive nights, indicating that something had gone wrong.
The egg was sent to The San Diego Zoo’s Pathology Lab for analysis. The results showed that the egg had been fertile and the chick had been developing normally until shortly before the expected hatch date. Why it died then is unknown, but this type of occurrence is not uncommon for even experienced breeders as observed in captivity. The fact that this was Condor 136 and 187’s first attempt, and that the egg was fertile, bodes well for a future breeding attempt for the pair. Next year, perhaps…
Meanwhile, both other nesting pairs seemed to be chugging right along. They were returning to their respective nests like clockwork, with increases in visitation right around the calculated hatch dates. This is exactly the behavior that we would expect to see in a successful nest, and this is just the type of thing that we depend upon to gain clues as to what may be going on in the nests when we can’t actually see into them. So, we began working on the assumption that we had two new wild chicks in Arizona. Our assumption was confirmed for the Vermilion Cliffs’ nest near the end of the month. On 24 June, crewmember Eddie Feltes verified a visual on a small grey puffball of a chick sitting with its mother, Condor 126. Ever the diligent observer, Eddie was also the first person to see the chick from that same nest last year. That chick, Condor 342, is doing wonderfully, and has since fully integrated into the rest of Arizona’s population. Hopefully the new chick will follow in its half-brother’s footsteps.
We haven’t yet obtained a visual on the chick in the Grand Canyon, although the parents’ behavior so far offers every indication that things are going well. Because of this behavior, and because this pair (Condors 123 and 127) have successfully fledged a chick in the past, we have no reason not to expect that there is a third wild condor chick in the Grand Canyon.
As the nesting pairs added new members to the population, the rest of Arizona’s condors continued to impress us with their foraging ability, finding a number of wild carcasses throughout the month. These were primarily mule deer and great sources of food for the birds, but one carcass was somewhat concerning. Condor 203 was found feeding on a coyote on the Kaibab Plateau, raising an immediate red flag for crewmember Frank Nebenburgh. Not knowing for sure how long or how much of the carcass Condor 203 had fed on, Frank collected the coyote carcass and brought it in for X-rays. We found that it contained a number of radio-dense fragments matching those of lead fragments that we have collected in the past. This is standard practice whenever we find a condor feeding on a coyote, as the coyote’s cause of death during this time of year is often found to be shooting. As in this case, bullet fragments frequently remain in the animal, potentially exposing a scavenger like a condor to acute lead poisoning. With the knowledge that Condor 203 may have been exposed to lead, we set out to trap him immediately, and we were able to get him within two days. Luckily, he seemed to have averted danger, as his blood levels did not indicate poisoning. To confirm that the levels were not on the rise, we held him for a number of days, retested, and released him when the blood lead levels remained in an acceptable range.
In addition to tracking birds to wild carcasses, we came upon a few incidences of birds homing in on food that we didn’t want them to find. Because many condors spend a lot of time in the Grand Canyon, there are numerous opportunities for visitors to the park to get great views of the majestic birds soaring in the canyon or overhead. The downside to this is that the birds’ occasional proximity to large groups of humans allow unknowing people to approach too closely, and, in the worst cases, attempt to feed the birds. This is potentially disastrous, as it causes the affected birds to begin associating humans with food, resulting in an animal that is eventually unfit to be in the wild population. Luckily, this doesn’t happen very often, but on one day in June we stopped three instances of people approaching and attempting to offer food to condors. If you happen to be visiting the northern Arizona/southern Utah area, consider yourself fortunate if you catch a glimpse of a California Condor, and enjoy the beauty of these spectacular creatures from afar. As with all wildlife, though, it is important to keep your distance and never offer them food. With everyone’s cooperation, we can continue to increase the California Condor population and help them remain as wild as possible.
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