Demand remains the same, and higher prices for the catch motivate fishermen to continue to overfish a declining resource.
Unregulated commercial fisheries have repeatedly destroyed stocks of numerous fish species around the world. It's a "Tragedy of the Commons."
This is NOT a case where a free market takes care of itself.
So explain to me why I've never caught a Sturgeon in Chesapeake or Delaware Bay, despite fishing in both bodies of water all of my life?
You don't charge more AND have demand stay the same. Demand will go down with higher prices.
I don't know enough about sturgeon to even comment on sturgeon and anyplace.