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We sit and look at eyries. In this case, one coastal nest, one Santa Cruz Mountains nest, and, one urban nest. Observer colleagues and I try to nail down hatch dates so that I can return to band at the right time.
There is little activity at the nest when falcons are incubating but there is plenty to entertain the patient watcher. The Coast. Backs to the ocean, we watched the eyrie as the sun slowly made its way over the top of the cliff that we watched. An osprey soared over from time to time and red-tailed hawks too. Whimbrels probed the sand at water’s edge. All the while a peregrine that we believed to be the female preened her plumage and the sun eventually illuminated her cliffside perch. For three and one-half hours the nearby eyrie appeared to be vacant. The peregrine made no move toward it. In fact, she never left her perch until an adult peregrine flew past traveling north. She followed making some half-hearted jabs at the passerby and then returned to her spot in the sun. (It is wonderful to see so many peregrines in the world!) Finally–and for just five seconds–the head of an adult peregrine that we believed to be the tiercel was visible above the protected ledge we had been watching intently. Five seconds out of four hours. Ah, incubation underway… We waited another half an hour and then packed up gear after a lovely morning on the coast.
The Santa Cruz Mountains. Many pairs of peregrines (more than 10) now make their home in this coast range. My friends–dedicated falcon watchers–found this pair several years back and have seen the pair at two different eyrie locations. They hiked the mountainous trails this year until they had a view of the nest site at eye level from quite a distance across the canyon. They sat staring at the ledge they believed to be the eyrie for two hours until they detected a movement and discovered they had been staring at a falcon’s tail feathers the whole time! They watched for four and one-half hours and saw her leave the nest only once and for just a few moments. They could hear the tiercel call from a distance. Again, no food going in so we assume eggs are still under incubation.
The urban site. Here, our peregrines use an old raven’s nest on the side of a building in an industrial area. Heat waves from a building in the foreground confuse the view. The tiercel wears a band that I hope to be able to read when I visit to band the young because access to the immediate area of the nest is only possible at the time of banding. We want to identify him. Staring at a building through a powerful spotting scope can sometimes draw the police, and it did. The officer who got the call happened to be a birder and so was fascinated by what he found–a happy ending to an initially tense situation. My friends stayed on until four and one-half hours in, the falcon left briefly and returned with some cached food dangling from one foot. When she landed on the edge of the nest, one tiny white head popped up informing us that at least one hatchling was in the nest. I’ll add that site to my calendar for banding!
We sit and watch nests. The world goes by and the peregrines tell us their story.
Falcons in the Santa Cruz Mountains nest a little later than the urban birds. We already have full clutches of eggs under incubation at San Jose City Hall (first egg March 7th) and San Francisco PG&E (First egg March 14th) where nest camera viewers (SCPBRG.ORG) are counting down to hatching. Other urban birds around the Bay are incubating as well.
It is probably safe to assume that the urban peregrines with a year around supply of rock doves or common pigeons are not constrained by the seasonal production of birdlife in the way that their “wilder” cousins must be. Certainly, urban peregrines are just as “wild” as those that nest in a remote mountain canyon, it is just that they live on artificial cliff faces and eat non-native birds.
When I traveled to one of the remote canyon sites this weekend the quiet of the place was almost complete. The waterfall at the head of the canyon has been silenced by the drought, and likewise the tree frogs that would multiply in vernal pools in any other year. It was silent except for the mournful wail of a female peregrine.
We looked for her by scanning all of the favored cliff face perches until our arms gave out from supporting binoculars. After about an hour, the male appeared in flight before the vertical face and settled on his mate’s back to copulate, revealing her position. After the brief act with wings fluttering, the male settled back into easy flight wheeling in a column of rising air. Soon enough, the female came to join him and both soared up, over a ridge, and out of our view.
Another occupied site to put on a lengthening watch list for the spring of 2014. Happily, sufficient food appears to exist to send one pair after another into their reproductive cycle. At banding time, we will learn whether the 2013 rate of success (avg. 3.5 young at 8 nests where banding occurred) is equaled in 2014.
Observing peregrines, whether in the city or mountains, is such a treat compared to the slog of negotiations with our state and federal permitting agencies. News on the outcome of a year of deliberations over the bridge birds when I know it. Stay tuned.