Publications

The variable lymphocyte receptors (VLRs) consist of leucine rich repeats (LRRs) and comprise the humoral antibodies produced by lampreys and hagfishes. The diversity of the molecules is generated by stepwise genomic rearrangements of LRR cassettes dispersed throughout the VLRB locus. Previously, target-specific monovalent VLRB antibodies were isolated from sea lamprey larvae after...

Information on the movement patterns of fishes is essential for managers that are making critical resource decisions. We examined the frequency of a keystone species, Chinook Salmon Oncorhynchus tshawytscha that migrated from different marine basins to the Nisqually River estuary, which lies within the southernmost marine basin (hereafter, “South basin”) in Puget Sound (Washington, USA)...

The California Department of Water Resources (DWR) requested analysis of juvenile Chinook salmon survival in the Sacramento-San Joaquin River Delta (henceforth identified as “the Delta”) as part of an effects analysis that will be included in an Incidental Take Permit (ITP) Application. This application is in compliance with the California Endangered Species Act (CESA) and Environmental...

Understanding drivers of temporal variation in demographic parameters is a central goal of mark‐recapture analysis. To estimate the survival of migrating animal populations in migration corridors, space‐for‐time mark–recapture models employ discrete sampling locations in space to monitor marked populations as they move past monitoring sites, rather than the standard practice of using...

In 2016, the U.S. Bureau of Reclamation (USBR) and California Department of Water Resources requested a reinitiation of consultation under Section 7 of the Endangered Species Act on the coordinated long-term operations of the Central Valley and State Water Projects. This resulted in a Biological Assessment released by USBR in 2019. In its analysis of the Biological Assessment for its...

We developed two quantitative PCR assays for use with environmental DNA (eDNA) to detect numerous species in the genus Cottus that are indigenous to the Pacific coast watersheds of North America. We conducted in vitro assay validations on ten Cottus species and 32 potentially co-occurring non-Cottus species. We demonstrate the efficacy of these assays by field testing eDNA samples...

In teleost fish as in mammals, humoral adaptive immunity is based on B lymphocytes expressing highly diverse immunoglobulins (IG). During B cell differentiation, IG loci are subjected to genomic rearrangements of V, D, and J genes, producing a unique antigen receptor expressed on the surface of each lymphocyte. During the course of an immune response to infections or immunizations, B...

The myxozoan parasite Ceratonova shasta is an important pathogen that infects multiple species of Pacific salmonids. Ongoing genetic surveillance has revealed stable host-parasite relationships throughout the parasite's endemic range. We applied Bayesian phylogenetics to test specific hypotheses about the evolution of these host-parasite relationships within the well-studied Klamath...

The prevalence of Ichthyophonus infection in Pacific herring Clupea pallasii was spatially heterogeneous in the southern Salish Sea, Washington State, USA. Over the course of 13 mo, 2232 Pacific herring were sampled from 38 midwater trawls throughout the region. Fork length was positively correlated with Ichthyophonus infection at all sites. After controlling for the positive...

Executive Summary The production of Klamath River fall Chinook salmon (Oncorhynchus tshawytscha) in northern California and southern Oregon is thought to be limited by poor survival during freshwater juvenile life stages, in part a result of Ceratonova shasta—a highly infectious disease that can lead to high fish mortality. Higher flushing river flows are thought to affect the...

Executive Summary In this report, we describe application of the Stream Salmonid Simulator (S3) to Chinook salmon (Oncorhynchus tshawytscha) in the Klamath River between Keno Dam in southern Oregon and the ocean in northern California. S3 is a deterministic life-stage-structured population model that tracks daily growth, movement, and survival of juvenile salmon. It can track different...

Stakeholder interests have spurred the reintroduction of the critically endangered populations of Chinook Salmon to tributaries upstream of Shasta Dam, in northern California. We released two groups of acoustically tagged, juvenile hatchery, late-fall Chinook Salmon to determine how juvenile salmon would distribute and survive. We measured travel times to Shasta Dam, and the number of...