2022 Tualatin Basin Wide Rapid Bio-Assessment

The Tualatin Basin Wide Rapid Bio-Assessment (RBA) project is a snorkel survey inventory and “...protocol designed to establish basin scale fish population estimates and distribution trends while analyzing habitat functionality.” (Bio-Surveys, LLC.). This updated snorkel survey will inventory 121 miles of priority stream habitat to help organizational and agency partners quantify the distribution and relative abundance of all juvenile salmon and steelhead species during the critical period of summer low stream flows. The new inventory will update the RBA efforts completed across the basin in 2013 and 2014.

In addition to juvenile salmonid population counts and extrapolated population estimates, the surveys account for fish passage barrier presence, beaver dam presence, notable cold-water sources, and quantify spawning gravel presence. This information contributes to a holistic picture of stream health in our basin and will provide grounds for determining focus areas in a rapidly changing climate. Additionally, this updated dataset is critical documentation which will serve the Tualatin River Watershed Council and partners in securing funding to support future projects, just as the original 2013-2014 RBA Final Report has been foundational for obtaining project funding for areas identified by the original surveys.

This updated inventory is a collaboration between the Tualatin River Watershed Council, the Tualatin Soil and Water Conservation District, and Clean Water Services. Surveys will be conducted by Bio-Surveys, LLC.