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

In Science Friday by Nick Chambers

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, but the so-called half-pounder.   …