Squanto Method for Fertilizing plants!
Here is a literal "Solution"!***Graphic images alert for any D/U visitors!***
Homemade Fish Fertilizer - Plants Go Crazy For This - JADAM JLF
I imagine that people could also make their own fish sauce, but people can research that on their own!
I fished for decades with my Grandpa. We NEVER tossed the fish heads when we cleaned fish - they were always buried right into the garden beds, or into the compost heap if we had been exceptionally successful that day. ;)