eDNA Monitoring of Ich in the Klamath River

he YTFP collected water samples from 3 locations on the lower Klamath River. These sites were selected based on their proximity to past ich outbreaks and ease of accessibility. Sampling occurred from June through October with water samples collected on a weekly basis using an automated water sampling machine (isco). Once collected, water samples were taken back to our laboratory to be filtered and the filtrate was frozen and shipped to OSU for analysis. We also planned to conduct 2-3 longitudinal sampling events. These events would take place over the course of a single day with multiple sampling locations spread out over the entire lower Klamath River. Ideally, longitudinal sampling would take place before, during, and after any potential outbreak of ich. This sampling strategy assists researchers in identifying any “hot spots” and possible sources of disease epizootics.



Currently, the YTFP ich monitoring program is through direct, lethal sampling of fish which can insensitive to early or light infections. Sentinel fish exposures are not possible during periods of high water temperature typically associated with Ich outbreaks. Water sampling for ich eDNA will provide valuable insight and compliment any ongoing ich studies and can be utilized as an early warning for disease outbreaks. This is the the most important aspects of this project. Working with OSU, the YTFP has the ability to relay specific real time information to water managers regarding the levels of Ich in the Klamath River. This tangible result can be invaluable when dealing with disease issues on the lower Klamath River.

Project Benefit: Information gathered during this project will be used as an early warning to identify possible disease outbreaks and/or fish die offs; such information can be used to inform water managers whether augmented flows are necessary in the late summer/fall to minimize disease risk.