Science Friday: Surviving heat, drought and ponded streams

In Science Friday by Nick Chambers

It is that time of year again. Heat wave after heat wave.   As summer progresses stream flows will continue to decline all across steelhead country, and in some cases, smaller tributaries will go dry. In other cases, streams won’t be completely dewatered; instead, they will become ponded. This occurs when flows diminish so much that the only remaining surface …

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Science Friday: How does catch and release affect steelhead?

In Oregon, Science Friday by Nick Chambers

Today we review a study on the impacts of catch and release angling on wild steelhead in the Bulkley River, the largest tributary to British Columbia’s legendary Skeena system. Conducted by Will Twardek and several others, this study looked into the effects of catch and release, air exposure and fight time on behavior and survival to spawning.   The study …

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Science Friday: Do these lipids make me look fat?

In Science Friday by Nick Chambers

For most anglers who have encountered both winter and summer steelhead, it’s abundantly clear there are differences between the two races of fish.   For one, they enter freshwater at different times of the year, although there is some overlap.   In addition, there are physical differences. Summer steelhead tend to be more fusiform — sleeker and more firm bodied …

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Science Friday: Do it once, do it twice. The tradeoffs of repeat spawning in steelhead

In Science Friday by Nick Chambers

We are back after a short break, after coming through a heavy dose of conservation work. That work, in part, helped convince the Washington Department of Fish and Wildlife and the National Marine Fisheries Service to re-open the iconic Skagit River for a catch-and-release season for wild steelhead. It feels like a new day has dawned for steelheaders in Puget …

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Stock Recruit Curves And Wild Steelhead, A Good Match?

In Science Friday by Nick Chambers

In several recent posts we have discussed the concept of density dependence and how it is used in fisheries management. Today we dive in deeper and talk about the stock-recruitment relationship, density dependence, and how the results of such models are applied to managing steelhead.   First, let’s define some terms. Stock refers to, in this context, a population of …

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

In Science Friday by Nick Chambers

  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 that found the spatial distribution …

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

In Science Friday by Nick Chambers

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 streams than among inland populations …

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

In Science Friday, Washington by Nick Chambers

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 only have we observed hundreds …