I'm just rambling here. Sort of a stream of consciousness ramble. Bear with me. 300,000,000 aren't going to go wild in their eating habits. A large percentage of those 330 mil live in large cities. In some catastrophic event, many of those will never leave that urban jungle they live in currently. They won't be able to travel. Lack of transportation, fuel etc will doom them to an animal’s life there. Game was killed off in the 1800 due in large part to market hunting. In the envisioned situation, market hunting wouldn't be a factor due to lack of refrigeration and transportation. Feral animals are proven to be adaptable and survivors. Wild pig will continue to explode in population. Cattle will proliferate in many areas. Texas and the southwest have proven to be a haven for the longhorn type cattle. Disease, starvation and fighting will kill off large percentage the people in North America. Most of the marginal living areas will see a huge drop in population with the first 18 months. For example, interior Alaska would be mostly depopulated within 18 months. Most folks wouldn't make it through the first winter, then how many of those left would make it through a second winter? Game would quickly rebound there. Without power, there is little refrigeration. So the hottest areas of the country would lose population quickly as well. Lack of long term food storage would be a big factor here as well. There are large portions of the plains states that actually meet the definition of "wilderness" due to lack of population right now. Those areas will only become less populated. Areas with a fairly rural population with a high percentage of hunters and gun owners will probably see a quick decrease in game. Think about places like Kentucky, Tennessee, and Alabama. Lots of folks there with ability to kill game close to home without travelling. The game in eastern Montana, North Dakota and South Dakota for example won't be hunted out because the distances from the major population areas are too great for people who are already hungry and without transportation. The first two months would see a big kill off of game in areas close to major population centers. The most rural areas, National Parks, BLM land, etc would actually probably see a boom in game animals. Too remote for large numbers of folks to get to for subsistence hunting. I think if the power went out today and never came back on then in 100 years there would be untold numbers of wild pigs, wild cattle and other large game. The bison would come back eventually also. Fences would rust and fall and no longer divide the plains after about the 30 years. What’s weird is the “exotics” held in many places in Texas and other areas would also be set free and would then be part of the ecosystem here. The Nilgai would fair well. Impala and others like that would too. I think the hardest part would be to make it past the first 18 months. If you could do that, you would probably be set for the most part. The first two months would be rough. Large die offs of people. Large numbers of people scavenging and looking for food anywhere and everywhere. After the first winter, the number of survivors would plummet. Roving bands of marauders and “warriors” would probably be in existence at that point. But there wouldn’t be much reason for them to come to areas without large numbers of weaker survivors for them to prey on. Staying hidden and out of site would be the key. If you couldn’t be seen from the road and had no lights or smoke to attract attention then you might be okay.
NGH