Water Parasite Sampling in Lower Trinity River - Hoopa Reservation

Objective: Determine density of relevant salmonid parasites in river water samples in the Trinity River and in the vicinity of its confluence with the Klamath River.



Project Description: The Hoopa Valley tribe will collaborate with Oregon State University to quantify C. Shasta spore concentration and Ich trophonts at two locations in the Klamath basin as part of a multi year whole basin project. OSU is seeking other funding for running the samples and these funds will be used to cover staff time and equipment that KBAO will not. The sampling will be conducted weekly from March to September coincident with other Klamath sampling and can be used to inform both the existing FASTA team and TRRP staff about conditions in the lower Trinity and Klamath Rivers. The sampling locations Hoopa will be responsible for are the mainstem Trinity in Hoopa and upstream of the confluence with the South Fork Trinity River.

We will determine the density of several waterborne parasites of salmonids in river water samples to include data collection during spring out-migration and fall in-migration. Weekly, 1L river water samples will be collected every 2 hours for 24 hours by an ISCO automatic sampler and pooled. After 24 hours, 4 1L samples will be taken manually from the 12L pool by Hoopa tribal biologists, and filtered within 24 hours. The concentrated captured material will be sent (FedEx or UPS overnight) to OSU for molecular analysis to determine the total parasite DNA in three of the four samples using qPCR (as per Hallett and Bartholomew 2006, Hallett et al. 2012 for C. shasta or Howell et al. 2019 for Ich); the fourth sample will be archived frozen. All water samples are simultaneously tested for assay inhibition. Water sample analysis will be rolling with updates available biweekly, weekly during salmonid outmigration.

Water collection will occur at the following two sites, weekly, March through September of 2024:

1. Hoopa Reservation on Trinity River (THR)

2. Mainstem Trinity upstream of South Fork (TBD; TXX)

The water samples will be tested by molecular assay (qPCR) for: Total Ceratonova shasta, C. shasta coho genotype II.

This project will provide early detection of C. shasta in the lower Trinity and South Fork Trinity Rivers . Early detection of C. shasta during the critical fall period while adult salmonids are returning to the system can provide managers with valuable time to act and try to mitigate the impact of the disease.