Did you know Seattle’s Ship Canal Bridge is home to a group of peregrine falcon chicks?

The 3-week-old chicks passed through a rite of passage Friday, getting banded with identification tags.

Banding, which involves putting small, metal bands on the chick’s leg, allows researchers to track migration patterns, life span, and behavior. It’s used by conservationists to keep the falcons safe and healthy, according to the Washington State Department of Transportation, which assisted with the banding.

Peregrine falcons are recovering from near extinction, and the bands also help crews understand which sites the birds are flocking to and which natural habitats to preserve.

The chicks were banded at three weeks old, because their legs are fully grown, but they have not developed flight feathers yet.

To access the peregrine falcons, workers climbed down the outside of the bridge using climbing harnesses and 20-foot and 40-foot ladders. Workers walked across a beam to approach the nesting box, where the falcons live, from both sides.

The birds were placed in a soft sided bag where their legs are measured and a band is slipped on their leg.

“The banding operation is a bit stressful for the falcon family – and sometimes for our workers high above the lake – but the end result is a win for everyone,” Mike Allende, WSDOT social media manager, wrote in a blog post.

Photos: Peregrine falcon chicks banded