On the morning of July 21, a 2 1/2-year-old grizzly bear emerged from a culvert trap, stepped into the sunlight and entered the rugged Cabinet Mountains near the Montana-Idaho border.

The 120-pound male marked the latest addition to a small, but growing population of grizzly bears in the far northwest corner of Montana, known as the Cabinet-Yaak Ecosystem. It was the 20th grizzly bear moved to the Cabinet-Yaak Ecosystem through a program that began in 1990 in an effort to save the population and boost genetic diversity. The last transfer into the ecosystem occurred in 2016.

This latest grizzly bear did not have any prior conflicts with humans. Montana Fish, Wildlife and Parks staff, in collaboration with the U.S. Fish and Wildlife Service, captured it recently in a remote area near Stryker Basin in the Stillwater State Forest. It was fitted with a GPS radio collar for future monitoring. It was released in a remote area west of Spar Lake in the Kootenai National Forest south of Troy.

The transfer program continues to be a success in an ecosystem that saw its grizzly bear population nearly vanish 30 years ago. In 1988, biologists estimated fewer than 15 grizzly bears remained in the Cabinet-Yaak, which spans approximately 1,000 square miles in the Yaak River drainage and 1,620 square miles in the Cabinet Mountains.

“Knowing what we know now from sampling, I think that was actually a very generous estimate. The number of bears were probably in the single digits,” said Wayne Kasworm, grizzly bear biologist for the U.S. Fish and Wildlife Service Cabinet-Yaak Ecosystem Program.

Today, thanks largely to the augmentation program that Kasworm helped establish, there is an estimated 55-60 grizzly bears in the Cabinet-Yaak Ecosystem. Illustrating the intent and success of the program, the third bear that was moved, a female in 1993, is responsible for at least 25 descendants through three generations. That female produced at least 10 first-generation offspring, which gave rise to at least 14 additional grizzly bears, and among those at least one offspring and counting.

“We are trying to increase the genetic structure of the population by bringing in unrelated individuals with no history of conflict,” said Kim Annis, FWP grizzly bear management specialist. “We have a really good family tree for the Cabinet Mountains that shows we might possibly have lost the population altogether without having continued this augmentation program.”

The recovery goal is 100 grizzly bears in the Cabinet-Yaak and hopefully over time the animals will link with surrounding yet separate ecosystems, the Selkirk to the west, the Northern Continental Divide to the east, the Bitterroot to the south, and British Columbia to the north.

“The ultimate goal is to see bears move into the Cabinet Mountains and reproduce. We haven’t seen documented gene flow or reproduction, and only in the last few years have we seen minimal movement into the Cabinet Mountains,” Kasworm said. “That’s another step forward.”