Publications

Kelp beds are prominent features of northeast Pacific coastlines. They are seasonal in nature, as are the communities that use them. Here, juvenile and adult Chinook salmon (Oncorhynchus tshawytscha) – key components of northeast Pacific marine food webs that link plankton and forage fishes to endangered killer whales – have just arrived at the coastal kelp beds (left) and are feeding on...

An analysis of daily water samples collected from an index site on Big Soos Creek, Washington indicated intra‐annual differences in the concentrations of waterborne Nanophyetus salmincola. Waterborne concentrations, quantified as gene copies/L, peaked during the fall (October–November 2016), decreased to very low concentrations over the winter (January–March 2017), and then increased in...

Telemetry has been an invaluable tool to improve our understanding of adult Pacific Lamprey (Entosphenus tridentatus) movements and to guide management approaches to protect and restore this species of concern. Juvenile and larval lamprey, however, are much smaller than adults, and have not been monitored with telemetry because available transmitters have traditionally been too large...

Background In fish tagging studies, tag size limits the size of fish that can be tagged, the fraction of a population that can be represented, and ultimately inferences that can be made about the study population, particularly when juvenile fish are the subject of interest. Introduction of an 8-mm passive integrated transponder (PIT) reduced the minimum taggable size of fish, but it has...

An evaluation was conducted to describe adult sockeye salmon (Oncorhynchus nerka) upstream movement patterns from Roza Dam to Cle Elum Dam in the Yakima Basin, Washington. Sockeye salmon adults that arrive at Roza Dam are currently trapped and transported upstream of Cle Elum Dam because upstream fish-passage facilities are not currently in place at the dam. However, these facilities are...

Terrestrial ecosystems are an important sink for atmospheric carbon dioxide (CO2), sequestering ~30% of annual anthropogenic emissions and slowing the rise of atmospheric CO2. However, the future direction and magnitude of the land sink is highly uncertain. We examined how historical and projected changes in climate, land use, and ecosystem disturbances affect the carbon balance of...

Thousands of screened water diversions throughout the Columbia River Basin of the Pacific Northwest are sources of entrainment (unintended diversion into an unsafe passage route), injury, and mortality for a range of fish species and screening criteria have been developed to reduce and mitigate these effects. Large knowledge gaps exist concerning the potential effects of these screens on...

The following report is divided into three sections each of which describes work conducted by different project cooperators. Chapter One describes smallmouth bass (Micropterus dolomieu) predation on subyearling fall Chinook salmon (Oncorhynchus tshawytscha) in Lower Granite Reservoir in 2018. Smallmouth bass abundance increased seasonally in shoreline habitats and was highest in the...

Fish are critically important to the welfare of this planet and its occupants, the health of both wild and captive fish populations paramount to our survival. This book presents the gross pathology of the most commonly encountered diseases and syndromes of fish in an organ system-based approach. It provides an overview of the diseases and disorders of tropical, ornamental, bait and food...

The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2018 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners...

Forage fish are small, abundant, schooling planktivores that form a critical link in marine food webs by transferring energy from plankton up to birds, fishes, and marine mammals. Forage fishes in Puget Sound include the iconic Pacific herring as well as lesser known species such as surf smelt and the Pacific sand lance. There are significant knowledge gaps regarding the basic life...

We studied some of the relationships between federally listed fall Chinook Salmon, Oncorhynchus tshawytscha, endemic Sand Roller, Percopsis transmontana, and non-native Smallmouth Bass, Micropterus dolomieu, in Lower Granite Reservoir on the Snake River. Because of its recent reappearance and population increase, the Sand Rollers could be filling the role of a “native invader” in the...