Yellowstone cutthroat trout once occupied habitat across Montana, Wyoming, Idaho, and slivers of Nevada and Utah. Now, they are in steep competition with nonnative fish for habitat and resources. To help give the Yellowstone cutthroat trout a leg up, GYC staffers volunteered to work with partners to remove invasive brook trout from Mill Creek, a slow-moving stream near Yellowstone National Park’s northern border.