Bull Trout were extirpated from the Clackamas River basin over 60 years ago. In 2011, a multi-agency reintroduction effort was initiated, with the goal of building a self-sustaining population of 300–500 adults. During the first phase of the program (2011–2016), 2,837 Bull Trout were translocated from the Metolius River basin. Each fish was fitted with a small identification tag (called a PIT tag) and released into areas of the Clackamas River basin with suitable habitat.
Since the releases ended, the Native Fish Investigations Section has tracked the progress of the reintroduction each year. We use several monitoring methods, including counting redds, detecting PIT tags with antenna arrays, testing water for environmental DNA (eDNA), and recording stream temperatures. Redd surveys show that Pinhead Creek, the upper Clackamas River, and Berry Creek can all act as areas for Bull Trout spawning. eDNA results suggest Bull Trout may also be using Roaring River.
Monitoring continues each year, with a focus on understanding what helps young Bull Trout born in the basin survive to adulthood. In 2024, 20 adults and 21 redds were counted across the basin. While these numbers have declined substantially from the peak in 2017–2018, the composition of the spawning population is shifting in an encouraging direction: at least 18 of the 20 adults detected in Pinhead Creek in 2024 appeared to be locally born, marking the third consecutive year of increasing recruitment of fish born in the basin.