Howling hounds picked up a cougar's scent and led researchers deep into the forest, where the steep hills were covered with cedars and ferns dusted with snow.
The dogs chased Lilu, an 82-pound (37-kg) cougar whose collar needed a new battery, up a tree. After being plunked by a tranquilizer dart, the groggy cat climbed down the tree and went to sleep. The team was able to swap her collar, examine Lilu, and then inject her with a drug to wake her.
It was part of a day's work for the Olympic Cougar Project, a partnership between a coalition of Native American tribes, a renowned cougar expert, and the Washington Department of Transportation.
As with the Washington project, the aim is to improve cougars' genetic diversity.
Both the California crossing and the Washington I-5 project are learning from one of the largest such undertakings, along a corridor of I-90 further north in Washington, which is about halfway through building 26 wildlife crossings along 15 miles (24 km) of the highway.
(Photo Editing Kezia Levitas; Additional Reporting Jack Ferry; Text Editing Diane Craft; Layout Kezia Levitas)