Category Archive: Science Friday

Science Friday: Steelhead fry party when the lights go off — but will they wake up high and dry?

In our last Science Friday post we took a look, in part, at the feeding behavior of bass. This week we are moving down in the feeding column to focus on catfish.   Just kidding. It’s all steelhead all the time here.   Today we review a paper by David Hines and several colleagues. The … Continued

Science Friday: Are some fish caught more than others, and if so, why?

We’re deep in the heart of winter steelhead season now. But if you’re like us, you are probably suffering from high-wateritis right about now — a common affliction for winter steelheaders.   Living on the Olympic Peninsula, I have it bad. Non-stop rain for days. Rivers punched. Headaches due to lack of chrome-ium. Conditions better … Continued

Science Friday: Space, time, and maximizing habitat capacity

All steelhead, all the time, here at Wild Steelheaders United. Over the past few weeks we have examined the scientific concepts and tools used to evaluate how productive a given stream can be for wild steelhead. Such assessments are an important component of managing a steelhead fishery — especially if the run in that watershed … Continued

Science Friday: The importance of both space and time in managing wild steelhead

  This is the third of four posts on the nuts and bolts of estimating wild steelhead populations, spawning success, and other key management variables.   First, we covered the concepts of carrying capacity and density dependence and how habitat can be used to estimate carrying capacity. Last week’s post shifted gears to review studies … Continued

Science Friday: Juvenile Density, Distribution and Habitat Capacity

By John McMillan New Year, new Science Friday! Last week we looked at the concept of carrying capacity, how it is estimated, and the most important habitat factors used to come up with those estimations. This week we shift gears a bit and review studies that illuminate how patterns in fish distribution can affect assumptions … Continued

Science Friday: The habitat that steelhead prefer, and how we use it to estimate capacity of rivers

By John McMillan How many steelhead can you fit into a given watershed? Put another way, what is the carrying capacity of a given watershed for steelhead? This question, and its answer, are important for steelhead fishery managers, and anglers, as we collectively try to rebuild wild fish runs up and down the West Coast. … Continued

Science Friday: The fate of stranded post-spawn adult steelhead

By John McMillan   One significant way in which steelhead differ from salmon is that O. mykiss have the ability to survive spawning and try to make the journey again. This behavior is referred to as repeat spawning.   Repeat spawner rates are highly variable among populations of steelhead, with rates being higher in coastal … Continued

Science Friday: Who’s who in the Elwha after dam removal

By John McMillan   We should not be surprised by steelhead and salmon rushing upstream to pass former dams. That is their nature — to push boundaries, access new habitat. Unbuild it, and they will come.   And come they have in Washington’s Elwha River, where in 2014 two old dams were taken down. Not … Continued

Science Friday: Why are half pounders declining in the Trinity River?

When anglers dream of steelhead, they mostly fantasize about fish that have spent 2-4 years in the ocean and return to freshwater to spawn as full adults, packing four or more pounds and brutish power into their physique. However, one of the most common forms of returning steelhead in some rivers is not the adult, … Continued

Science Friday: Behavioral Thermoregulation

Most steelhead anglers know that the family of fishes called salmonidae (trout, char, salmon and whitefish) are highly sensitive to water temperature and quality. These fishes require cold, clean water to thrive. But what happens to them when water temps become unfavorable? As you might expect, they seek out places in the river that regain … Continued