Peregrine Patrol helps keep birds safe

A volunteer team of people from several organizations, including the docent crew in Mount Diablo State Park, is gearing up for the peregrine falcon nesting season in the pinnacles of Castle Rock Park.

For the last two years, this team has helped keep climbers and hikers out of the closure zone – which encompasses the rocky spines and humped outcrops of this eye-popping formation. The area protects the falcons while they court, mate, nest and raise their young.

Peregrine falcons are the fastest animals on earth, capable of diving at more than 200 mph to capture smaller birds – their main prey. It’s quite a sight to see a peregrine dive, especially in light of the drop in peregrine populations when the pesticide DDT was used widely in the United States.

It was banned in 1972, but not before the birds disappeared across large parts of the country. Only one nest could be found in California in 1970.

Peregrines have recovered slowly but steadily. California now has 400 nesting pairs, helped along by humans. Now they nest every year in one rocky concavity or another at Castle Rock, sometimes successfully, sometimes not. Last year, the eggs never hatched. It could have been due to infertility, parasites or human disturbance.

Whatever the answer, this year takes on deeper significance. The Peregrine Patrol Team will work to reduce human disturbance of the birds, the only potential cause of last year’s nest failure that the team can hope to alter.

Peregrines are sensitive to people. They fly off the nest, fail to feed their young and sometimes abandon the nest altogether.

Castle Rock Park, an East Bay Regional Park, offers the main access points to the rock walls, which are in Mount Diablo State Park, just across Pine Creek. The two parks cooperate to protect the falcons, and the closure area is clearly marked. But with close to 100,000 visitors per year in Castle Rock Park, many hikers still scale the rocks. Most don’t know about the birds.

This coming season, volunteers will concentrate on talking to hikers. Patrol members will ask them if they realize there are peregrines there and if they’ve seen them.

The team will point out the birds when they can. Sometimes it’s pretty easy: Peregrines are really noisy birds. Even when all is well, they chatter and screech and scream. And when you see them slice across Pine Canyon on their knife-like wings, you won’t forget it.

Staci Hobbet is a docent with the Mt. Diablo Interpretive Association. You can send email to her at anastasiahobbet@gmail.com