Question: how do pearl mussels populate in rivers

Karen answered on 6 Nov 2018:

That’s a great question, and the answer is a bit complicated but really interesting! A parent mussel releases 10 million baby mussels at one time (this is called broadcast spawning). A passing fish (such as a salmon) will breathe in some of the small mussels as it swims past. The small mussels will live on the gills (the breathing parts) of a fish until they are large enough (6 times bigger) and then they drop off and dig into the gravel at the bottom of a river, where they can grow on for another 100 years if undisturbed! It’s a great way for the mussels to populate the rivers, as they have no feet and can’t swim, they use the salmon to get around instead and spread out so they can get a good patch of food and oxygen 🙂 I hope that answers your question but let me know if you’d like to know anything else!