Peregrine Falcons at UC Davis Medical Center | UC Davis Health

For the fourth season, a peregrine falcon family living atop UC Davis Medical Center has grown. Two chicks hatched in the nest and were banded by falcon experts from UC Santa Cruz for research. Stay tuned to watch the chicks grow up and leave the nest!

Since at least 2015, peregrine falcons have made their home at the medical center. Their nest is located a safe distance from the hospital's busy helipad.

Peregrine chicks change very rapidly once they emerge from their eggs. Weighing about 1.5 ounces at birth, the tiny chicks are feeble and slightly pink as their white downy feathers fill in. Since they can't regulate their own temperature for the first week or so, a parent (mostly the mother) will stay with them to keep them warm.

Within five days, a chick's weight will double. The siblings will continue to huddle and sleep in what looks to be a furry white pile. But they can also sit up and eat.

After about 14 days, the chicks start walking around and eating with enthusiasm, as mom and dad fly in and out with tasty morsels.

Within three weeks, the chicks are typically very active. By mid-June, they'll be flying and leaving the nest.

About the Peregrine Falcon

The peregrine falcon mom at UC Davis Medical Center has been keeping a very watchful eye on her four new nesting chicks. (Photo by Ken Waller, UC Davis Health)

The peregrine falcon was previously on the federal list of Endangered Species and was one of the first birds to be placed on California's Endangered Species List. The raptor was removed from the federal list in 1999, thanks to effort by The Peregrine Fund and others. The ban of DDT in 1972 across the U.S. also helped the species recover, leading to its removal from the state Endangered Species List in 2009.

Experts estimate the first-year survival rate for the chicks will be about 50%, as urban falcons face hazards such as injury, illness, and predators. The young birds typically begin flying away from the nest at the medical center sometime in mid-June. Experts say the birds usually stay in the area an additional month while their parents continue to feed them and encourage them to hunt.

Here are a few other facts about peregrine falcons:

• Scientific name: Falco peregrinus
• Body length: 13-20 in (33-50 cm)
• Wingspan: 31-48 in (78-122 cm)
• Weight: 1 to 3.5 lbs (0.4-1.5 kg)
• Like many raptors, peregrine falcon females are larger than males.
• Peregrine falcons can hit top speeds in flight of 200 mph and are considered the fastest animal on earth.
• Peregrines don't build typical nests like other birds, but instead lay eggs in a shallow indentation on the edge of a high cliff or other man-made structure, like a building or bridge.
• Baby peregrine falcons can start flying at 43 to 44 days old.
• Peregrines typically prey on small- to medium-sized birds, like songbirds, ducks, doves and pigeons. They are also known to feed on small reptiles, mammals and bats.

To learn more about the peregrine falcon and other birds of prey, check out the California Raptor Center at UC Davis and the California Department of Fish and Wildlife.