I don’t know what the stats are on sport fishing in Michigan but I guarantee its in the top 5 moneymakers for the state.
I have some relatives in MI and know it’s a huge employer...I would think that once you add in all the preipherals i.e. fishing lodges, boat dealers/rentals, charters, etc. you’re talking big $$. A lot like here in southern LA...except more ice and less ‘gators :-)