SCPBRG's Role in the Peregrine's Recovery
For our part, the SCPBRG program to assist with the peregrine falcon recovery in California, Nevada, and Oregon was founded in 1975. It began in earnest with the fostering of two peregrine chicks to a pair of peregrines at Morro Rock that were incubating dead eggs in 1977. These two chicks were flown to California all the way from The Peregrine Fund’s captive breeding facility in Ithaca, New York. At the time, statewide surveys in California indicated that only a handful of known peregrine falcon nest sites, or eyries, remained occupied. The decline was estimated to exceed ninety percent. SCPBRG aggressively pursued a peregrine falcon captive propagation program at its UC Santa Cruz facility, fostering the resulting young into unproductive remnant nests, or releasing them at hack sites at vacant peregrine nest cliffs.
In order to salvage thin-shelled wild eggs that would likely be broken by the incubating adults, we climbed to their eyries, substituted dummy eggs for the thin-shelled eggs, and hatched as many eggs as possible in our laboratory. Chicks were fostered to these wild pairs, allowing them to be productive again.
During the height of our peregrine falcon captive breeding and management activities, SCPBRG employed over 50 permanent and seasonal staff per year. These included students and other temporary employees who camped out for weeks or months to observe nest and hack sites, and a core group of laboratory and field biologists who led activities. We also conducted tours of our facility, allowing thousands a first-hand look at a hands-on endangered species recovery program.
By 1992, when we closed our captive propagation facility and labs, almost 800 peregrines had been released at our hack sites, fostered into wild peregrine falcon eyries, or cross-fostered into the nests of the more common prairie falcon. Many of these released falcons had become members of the 113 pairs known in the state that year. Today, we continue to release peregrine falcons at a few sites in California to mitigate various potential human impacts on nesting peregrine falcons and in some cases to salvage young from urban nest sites such as bridges where survival at fledging is poor. We continue to monitor the progress of the wild nesting population.
We estimate that today the peregrine falcon breeding population in California exceeds 250 pairs, and we believe that a robust population of "floating" (as-yet unpaired) adults exists to replace individuals lost from the breeding population. In areas where surveys continue, numbers of pairs are slowly but steadily increasing.
At SCPBRG we are proud and gratified to have played a role in the recovery of this magnificent species.