So, with rising demand you'd expect rising prices which would in turn suppress demand. Unless the object in question becomes a luxury good, in which case rising prices would in turn contribute to an increase in demand due to conspicuous consumption (can't be sure of the net effect but I'd speculate it'd be an increase or flattening of demand at worst).
What would be the economic solution to this problem? One way would be a moratorium but that seems politically unpalatable. One could hope that a previously sidelined fish makes a comeback and replaces Bluefin as the sushi staple; controlling tastes seems hard if not impossible so that would be unlikely as well. Maybe convince a celebrity chef to endorse a cheaper (and less endangered) fish?
What would be the economic solution to this problem? One way would be a moratorium but that seems politically unpalatable. One could hope that a previously sidelined fish makes a comeback and replaces Bluefin as the sushi staple; controlling tastes seems hard if not impossible so that would be unlikely as well. Maybe convince a celebrity chef to endorse a cheaper (and less endangered) fish?