Hunting won't be a viable method for replacing the majority of calories in one's diet in any scenario in which the public has to resort to finding such a replacement. Small game is only capable of supplanting other calorie sources, and although that role as a supplement is incredibly important in terms of nutrition, it can't serve as Plan A no matter how many squirrels and ducks you see in the park during "peacetime". Large game, which means white tailed deer for 95% of Americans, is viable in terms of calories per successful hunt but the success rate of hunting will plummet the longer any food-insecurity scenario continues. The population of white tailed deer is enormous (15,000,000) but the population of people capable of hunting them is large enough to absolutely annihilate that population in mere months.
Just doing some napkin math but several sources state the average carcass of a northern state buck yields 72lbs of meat. Does outnumber bucks and are far smaller (plus southern deer are far smaller) but let's be conservative and say the average is 60lbs of meat per carcass. Multiply that by the FDA approved # of calories per pound of ground venision which is 712, and you get 42,720 calories. Let's say you have to feed a family of 4 and you're fine with a starvation diet of 1,400 calories per day. That deer only provides you with 15 days of food assuming it only needs to provide for half that already limited calorie intake. Make that ~11 days if you want to maintain a 2,000 calorie diet with venison being half. Now picture the ramifications of that math as it plays out over a population of millions of families with an experienced hunter in the household and their need to take 2+ deer every month. Not only do you still need additional sources for the other half of your calorie intake, you'll need to replace the portion satisfied by venison fairly quickly as the deer population is hunted into near extinction.
Basically, hunting serves as an excellent way of supplementing your diet in such a scenario but it is by no means a complete solution over any timeframe and it becomes completely non-viable withing a surprisingly short window of time.
Just doing some napkin math but several sources state the average carcass of a northern state buck yields 72lbs of meat. Does outnumber bucks and are far smaller (plus southern deer are far smaller) but let's be conservative and say the average is 60lbs of meat per carcass. Multiply that by the FDA approved # of calories per pound of ground venision which is 712, and you get 42,720 calories. Let's say you have to feed a family of 4 and you're fine with a starvation diet of 1,400 calories per day. That deer only provides you with 15 days of food assuming it only needs to provide for half that already limited calorie intake. Make that ~11 days if you want to maintain a 2,000 calorie diet with venison being half. Now picture the ramifications of that math as it plays out over a population of millions of families with an experienced hunter in the household and their need to take 2+ deer every month. Not only do you still need additional sources for the other half of your calorie intake, you'll need to replace the portion satisfied by venison fairly quickly as the deer population is hunted into near extinction.
Basically, hunting serves as an excellent way of supplementing your diet in such a scenario but it is by no means a complete solution over any timeframe and it becomes completely non-viable withing a surprisingly short window of time.