Eclipse, a 3-year-old peregrine falcon, was in trouble.
The bird had found its way into a water treatment building at the WE Energies Oak Creek Power Plant.
Perched in the building's rafters, the bird had shown no inclination to fly down and out open doors.
"They're basically trapped once they get inside," said Greg Septon of Muskego, one of the nation's leading falcon researchers.
No one knows when the female falcon flew into the building. At least four days had passed since it was first observed inside.
But as to the "why," Septon said Eclipse was probably following its favorite meal - a pigeon.
Septon decided to use the same lure to get it out.
Called to the site on Oct. 30 to help extricate the peregrine, Septon looked but found no pigeons in the building. It seemed the falcons had been doing a very good job of keeping the local "rock dove" population in check.
Eclipse raised three chicks in a nest on one of the stacks at the Oak Creek site this year with her mate, Scott.
So Septon turned to Jim Kitzman of Oak Creek, a falconer who also keeps racing pigeons.
Kitzman lent Septon one of his high-end homing birds.
"He was leery, but in the end gave me one with the understanding I would do all I could to keep it alive," Septon said.
The pigeon had soft leather anklets, or jesses, attached.