I have been reading about medieval fishing, and how it was so widespread they had to institute the first laws limiting how many fish could be taken. This got me thinking about the Pacific Northwest. Salmon come up river to spawn, and many are eaten by bears, effectively moving nutrients from the sea to the surrounding land. I don't recall the exact figure, but I know the forests of Vancouver are dependent on the salmon run. My question is if something similar happened in Medieval Europe, with humans instead of bears, and where I could read more about it.
I ask here in meta because I'm not sure if it needs more development or if it even belongs on Biology.SE.