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To aid a research project, Idaho steelhead anglers are once again being asked to watch for tagged steelhead they might catch during the 2020-21 steelhead fishing seasons, and report tagged fish if they catch one.

Steelhead trout stir up the sediment of the river bed when building their spawning pits, thus influencing the composition of the river bed and the transport of sediment. Until now, this process could only be studied visually, irregularly and with great effort in the natural environment of the fish.

Microplastic pollution in marine environments is concentrated most highly in coastal habitats, especially fjords and estuaries, according to a new review article.

Adult chinook salmon are returning from the ocean to rivers along North America’s West Coast at younger ages and smaller sizes (about 5 to 8 percent in the Yukon River) since the 1970s. The smaller size is resulting in a drop in reproductive potential for female salmon by 24 to 35 percent, based on total egg mass per female, according to a recent study.

Fish exposed to very low levels of chemicals commonly found in waterways can pass the impacts on to future generations that were never directly exposed to the chemicals, according to Oregon State University researchers.

The Center for Whale Research reported in January 2020 that L41, also known as “Mega”, is missing from L-pod -- one of three family groups of the endangered Southern Resident Killer Whales.

A recent study found that the stray rates of returning natural origin salmon and steelhead in the upper Columbia River basin differ by river basin, sub-basin and by stream, with the larger the area the lower the straying percentage.

Researchers in Oregon State University's College of Agricultural Sciences have taken a step closer to solving one of nature's most remarkable mysteries: How do salmon, when it's time to spawn, find their way back from distant ocean locations to the stream where they hatched?

University of Colorado researchers have developed a method that could enable scientists to accurately forecast ocean acidity up to five years in advance. This would enable fisheries and communities that depend on seafood negatively affected by ocean acidification to adapt to changing conditions in real time, improving economic and food security in the next few decades.

Three years of “health check-ups” on Oregon’s summer resident gray whales shows a compelling relationship between whales’ overall body condition and changing ocean conditions that likely limited availability of prey for the mammals, a new study from Oregon State University indicates.

In a sampling of fish from a creek that flows into San Diego Bay, nearly a quarter contain microplastics, according to a new study published in the journal PLOS ONE. The study, which examined plastics in coastal sediments and three species of fish, showed that the frequency and types of plastic ingested varied with fish species and, in some cases, size or age of fish.

The physical condition of a female steelhead at its first spawning can predict the ability of the fish to spawn a second time a year later, according to a recent study that measured body chemicals and condition in female hatchery fish.

For the first time, researchers have used radar and other tools to accurately measure the volume of snow produced through cloud seeding.

Steelhead reared in a hatchery for one year consistently outperformed males reared in the hatchery for two years when competing for spawning opportunities, although one and two year old female steelhead did not differ in their ability to produce offspring, according to recent study.

Chinook salmon smolts that rear in upper Willamette River reservoirs grow much faster and are larger than their counterparts that rear in streams, according to a recent study.

There's a long-standing belief in the freshwater fishing community that once anglers find it too hard to land a particular fish for their dinner plate, they either move on to fishing for different species or fish in new waters, giving depleted populations time to rebound.

The Great Alaskan Earthquake of 1964 and the tsunamis it spawned may have washed a tropical fungus ashore, leading to a subsequent outbreak of often-fatal infections among people in coastal regions of the Pacific Northwest, according to a paper co-authored by researchers at the Johns Hopkins Bloomberg School of Public Health and the nonprofit Translational Genomics Research Institute.

Technological advances are allowing commercial fishing fleets to double their fishing power every 35 years and put even more pressure on dwindling fish stocks, new research has found.

To a certain extent, coho salmon smolts can withstand temperatures somewhat higher than previously thought to be optimal for survival and growth, and, in fact, will even grow faster and larger in higher temperatures, although survival may drop. However, the important variable in their growth over summer periods is the availability and abundance of invertebrate prey for the young salmon to eat, according to a recent study.

Three new viruses—including one from a group of viruses never before shown to infect fish—have been discovered in endangered chinook and sockeye salmon populations.

In what the lead author says is a “thought experiment,” a new study says that solar and photovoltaic arrays – many on the site of former dams – could produce enough power to replace most hydroelectric dams in the United States, giving salmon, sturgeon, shad and other fish runs unimpeded access to spawning grounds.

A recent study combined ecological analysis with the social sciences, identifying a critical link between fish abundance, angler behavior and management actions.

A new study finds that the world's marine fisheries form a single network, with over $10 billion worth of fish each year being caught in a country other than the one in which it spawned.

Recent research documented transoceanic migration in Pacific Lampreys for the first time, with one tagged lamprey traveling from the Bering Sea to the Columbia River.

Just over one-third (37 percent) of the world's 246 longest rivers remain free-flowing, according to a new study published in the scientific journal Nature.