What is a B-Run Coho Salmon?

Here in SW Washington we love Coho Salmon. Sometimes you hear us and other anglers refer to “B-run” Coho and how much we love chasing them. We are always seeking to educate and if you don’t fully understand what we mean by "B-run" we hope this quick blog helps! A "B-run coho" refers to a specific type or run of coho salmon (Oncorhynchus kisutch) in the Pacific Northwest, particularly in the context of salmon fisheries. Coho Salmon, also known as silver salmon, have two primary runs or migrations in many regions: the A-run and the B-run. These runs are characterized by differences in the size, timing, and sometimes the life history of the salmon. Note that not all systems have both A-run and B-run and no matter the run you should be fishing!

Here's what "B-run coho" typically signifies:

  1. Size: B-run coho salmon are generally larger in size compared to the A-run coho salmon. They tend to be older and have spent more time in the ocean, which allows them to grow larger before returning to their freshwater spawning grounds.
  2. Timing: B-run coho salmon typically return to their spawning grounds later in the season compared to the A-run coho. Their migration and return coincide with a later period in the year.
  3. Life History: Some B-run coho may exhibit variations in their life history, such as a longer time spent in the ocean or different spawning behavior. These variations can be influenced by factors like food availability, ocean conditions, and competition with other salmon species.
  4. Fishery: In fisheries management, distinguishing between A-run and B-run coho can be important for regulating the harvest of these salmon. Managers may implement different regulations and quotas for each run to ensure the sustainability of the salmon population.
  5. Agression: Now this is where things get less scientific but ask anglers and you will find this to be true. For one reason or another B-run coho seem to be far more eager to chase and attack a fly. Simply put they won't miss the opportunity making them one of our favorite fisheries! 

It's worth noting that the specific characteristics of A-run and B-run coho salmon can vary by region and even within different river systems. Fisheries managers and biologists closely monitor these runs to assess their health and abundance and make informed decisions about conservation and harvest management. If you have not caught a salmon on the fly coho are an amazing place to start especially here in SW Washington! Historically speaking we start to catch B-run fish in early November even into Jan 1! Good luck and shop Spawn for all your Coho Salmon needs!

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