SAN JOSE (KCBS) – Five new peregrine falcon chicks have hatched in the Bay Area, including four in San Francisco and one in San Jose.

In San Francisco, four chicks were hatched in the nest atop the Pacific Gas and Electric building. And on top of San Jose City Hall, an egg belonging to celebrity falcon “Clara” has hatched, with three more little falcons expected in the coming days.

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Glenn Stewart, a biologist at the Predatory Bird Research Group at the University of California, Santa Cruz said these chicks will grow extremely fast, achieving their adult size in just three weeks.

“It all happens very fast. Within six weeks, the babies you see online as fuzzy little golf ball size birds will fly away from the nest,” said Stewart. “They’ll achieve their adult size and weight in three weeks. Then they grow feathers and then they fly.”

Stewart said he will climb to the San Jose City Hall ledge where the nest sits when the chicks are three weeks old and put bands on their legs so that scientists can track them and determine their health and gender.

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He said it wasn’t long ago that the birds were nearly extinct in California.

“What we do now is study them from the perspective of being an indicator of ecosystem health. So long as there are a stable number of peregrines continuing to breed successfully every year, we’re happy,” said Stewart. “If we start to see the population fall out, we know that there’s something wrong and we try to figure out what it is.”

Stewart said in 1970, there were just two pairs of peregrines left in California. Now, there are 31 pairs in the Bay Area alone.

You can see live video from web cams fixed on the nest in San Jose and San Francisco.

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