SAN JOSE (CBS SF) – A falcon researcher rappelled more than 280 feet down the face of City Hall Tuesday to give a high-rise checkup and attach tracking devices onto the latest pair of peregrine chicks to be born on a nest wedged into a ledge high above San Jose.

It wasn’t the first time Glenn Stewart, the Director of the UC Santa Cruz Predatory Bird Research Group, has scaled down the side of a building to access a nest.

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“We band peregrines all over the Bay Area,” he said.

Tuesday’s high-rise effort was to check on the latest offspring of famed City Hall falcons Clara and Fernando.

The pair have raised several chicks over the years under the watchful eye of a webcam.

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Stewart said the latest chicks were a male and female, look healthy and had been hatched 23 days ago.

Peregrine falcons have made an amazing recovery from the edge of extinction in the 1970s. Use of the now banned pesticide DDT killed the birds in record numbers.

Stewart said there were only two pairs of peregrines in the west in 1970. The population of falcons has now recovered enough that the peregrines are no longer on the endangered species list.

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The UC Santa Cruz program led one of the major recovery efforts and continues to monitor the birds’ health and movement using bands attached to their legs.