My dad used to do this when i was a kid. He would bring home through fish he didn't want or like, like say a carp or bull head. And bleed them out for a while. Then dig a hole in the garden to throw the fish in. Said it was fertilizer. Thoughts on this

Not unless you want every animal in the neighborhood digging your plants up. I did that once when planting peach trees and the next morning my peach trees were all dug up---I mean completely out of the ground. I replanted them in the same spot and they tore them out again. I couldn't plant anything in those holes for rest of the year.

Yeah, I don't want that to happen. Lol not good.

Dave, my parents also bury fish scraps in the ground! This is called tench composting and was used by Native Americans.

But as Lorn said, it can invite raccoon to come and tear up your garden. My parents bury their food scraps quite deeply, which seems to help with the smell.

Any animal waste works....the bone calcium may be the richest source of nutrients. I had sheep for a numbefor of years. If I dispatched one, anything I did not want to cook was buried deeply. It seems that tomatoes especially flurrished with this method....and possibly the smell of tomato greenery covered the allure to be dug up.