Four Male Falcon Chicks Thriving at City Hall
- UC Santa Cruz biologists banded four male peregrine falcon chicks at San Jose City Hall on May 13, after the birds hatched healthy atop the downtown nest. - Four chicks is the key number: researchers said all are male, and ABC7 reported each also received a radio transmitter. - In about six weeks, UC Santa Cruz volunteers will begin fledge-watch shifts near City Hall as the chicks make first flights.
Four peregrine falcon chicks hatched at San Jose City Hall are healthy, all male and now banded for tracking, according to UC Santa Cruz biologists and local reports. Researchers entered the nest on Wednesday morning, May 13, to weigh and band the chicks as part of a long-running Bay Area monitoring program. ABC7 reported that each chick also received a radio transmitter, a first for the program at this nest. The birds are expected to make their first flights in about six weeks, with volunteers preparing to watch the area below City Hall during that period. ### Why are biologists climbing into a City Hall nest? The City of San José says peregrines have nested on an 18th-floor ledge at City Hall since the camera project began in 2007, and the site is part of a broader research partnership with the Predatory Bird Research Group at UC Santa Cruz. Each spring, the city says, PBRG biologists enter the nest to check chick health and attach leg bands that can identify the birds later in life. (nbcbayarea.com) UC Santa Cruz says its Bay Area peregrine monitoring program has been banding young falcons and tracking their movements, survival and productivity for 25 years. The group says the work relies on student and volunteer observers and is designed to detect threats facing California raptors. ### What do the bands and transmitters actually tell researchers? (sanjoseca.gov) ABC7 reported that Zeka Glucs of the Santa Cruz Predatory Bird Research Group and colleagues banded the four chicks at about 8 a.m. on May 13. The station said each chick was also fitted with a radio transmitter attached to its leg so researchers can remotely track its movements and location after it leaves the nest. (predatorybirdresearch.sites.ucsc.edu) The City of San José says leg bands also let viewers and researchers tell the young birds apart as they grow on camera and eventually take their first flights. That matters at a nest that is watched both by scientists and by an online audience following the live feeds. ### Which falcons are raising these chicks? The City of San José identifies the current adult pair at City Hall as Hartley and Monty, two unbanded peregrines that settled at the site in the 2023 season. (abc7news.com) The city says the nest cams now provide three public views — ledge, nest and roof — after a new camera system was installed in 2024 by PBRG and the Institute for Wildlife Studies. (sanjoseca.gov) NBC Bay Area reported on May 13 that the four chicks were doing well and that their parents would continue feeding and protecting them until they can hunt on their own. The station said the young birds will eventually leave the nest for good after fledging. ### Why are volunteers posted near City Hall when the chicks start flying? (sanjoseca.gov) San José Public Library event listings for April 2026 said Santa Cruz Predatory Bird Research Group volunteers work each May and June near City Hall to observe and, if needed, rescue fledgling peregrines learning to fly. A separate library listing describing the City Hall nest said UC Santa Cruz and “Fledgewatch” volunteers have supported birds at the site for 20 years. (nbcbayarea.com) SFist, citing the same monitoring effort, reported that volunteers are expected to station themselves outside City Hall when the chicks begin fledging to make sure none come down before they are ready. That watch period lines up with the roughly six-week timeline reported by NBC Bay Area for first flights. (sjpl.bibliocommons.com) ### How important is this nest in the Bay Area program? The City of San José says the City Hall site is one of more than 30 active nests in the San Francisco Bay Area that are part of the PBRG peregrine monitoring program. UC Santa Cruz describes the program as ongoing regional surveillance of peregrine breeding, survival and dispersal. ABC7 reported that researchers see the San Jose nest as especially important as avian flu has reduced the number of healthy breeding peregrines at monitored Bay Area sites. (sfist.com) The station said that of 47 nests monitored in 2020, 11 remained occupied by healthy breeding adults. In the next phase, the four chicks will stay on camera as they feather out over the coming weeks, and volunteers are expected to begin fledge-watch shifts near San Jose City Hall in May and June before the birds’ first flights around late June. (sanjoseca.gov) (nbcbayarea.com) (abc7news.com)
