When Europeans were coming to the Americas they were expecting to find a huge mass of ancient, old-growth forests. These types of forests are thick with undergrowth and have large, old trees that often provide dense canopy. Once having arrived, these travelers were surprised to find forests much like their own, which had been managed or disturbed in some way by people. The reason, of course, is that there were humans in the Americas too, and had been for thousands of years.
There are various methods of agriculture and one of the common methods used by the Native Americans on the east coast was not the standard European monoculture row method. Instead, areas in a forest would be burned and many different types of seeds would be planted. This allowed different plant species to grow at one time, shading and protecting the soil until the next species would grow, sort of like they were taking turns. And while the fruit of the plants would be collected, those parts not needed would be left on the site to disintegrate and return to the soil, providing more nutrients. After a few years a new spot would be chosen, leaving the old spot to be returned to the forest.
What does all this have to do with wildlife? A lot, actually. The Native American method of agriculture actually encouraged the deer populations by controlling the thick undergrowth that could bar movement by deer as well as providing new growth and fresh shoots for them to eat. The Natives, then, had a healthy supply of deer for food. It was a win-win situation in many cases.
Anyone that may live in the Northeast of the U.S. would likely know the white-tailed deer (Odocoileus virginianus) population around here is commonly quite robust, sometimes to the point of being hazardous. This occurs whenever populations, regardless of species, surpasses the ecosystem’s carrying capacity. (Check out the article: Deer Carrying Capacity: Too Few, Too Many, and for Whom?) People in the area might be surprised to learn that at one time this same species of deer had a population so low that they were considered threatened, both from the destruction of their habitat for farm land as well as large-scale hunting, and that regulations had to be put in place to protect them. Now, regulations are put in place to try and control their numbers. New York State has an active Deer Management Program.
(This is a similar situation to other species in other areas. For example, much of the wildlife in South Africa can be found in parks and ranches and these enclosed locations do not always have predators within their communities to aid in controlling population. Hunting (commercial, in most cases) is then used to control the herd size while generating income for the ranch. This is often the case for antelope species such as impala (Aepyceros melampus).)
The biggest reason the deer population has increased so much is a large decrease in predators. Here in the Northeast they had three main predators: cougars/mountain lions, wolves, and humans. In New York both cougars and wolves are classified as extirpated, which basically means they are locally extinct and no longer can be found in the wild. Both species were purposely pushed to this state of local extinction by white settlers which had believed that these animals were inherently dangerous and provided a threat to livestock (this is still a common belief that has ranchers fighting for the removal of wolves in states with healthier populations) and competition for fur-bearing species. With two out of the three top predators of deer gone, that leaves only humans, and hunting/trapping has slowly reduced in popularity over the years.
Here in the United States, hunting is one of the main tools of wildlife population management. State regulators, such as the NYS Department of Environmental Conservation, conduct population and health surveys and compare these numbers to what had been determined to be the habitat’s carrying capacity for a particular species, for a health ecosystem. Instead of culling, wildlife birth control, or other various population control methods, regulators instead issue hunting or trapping permits and bag limits (how many animals are allowed to be killed, sometimes also divided by sex). The number of permits and bag limits change based on the population of the species in that year, and how many animals could ideally be taken in order to keep a healthy population with genetic diversity but also reduce the numbers enough to reduce wildlife-human conflict (such as species being hit by cars) and starvation.
Hunting itself has become more of a controversial issue now that most people obtain their food from the grocery store and not by hunting or raising their own food. This separation from where our food comes from can make some people ignorant in this regard. Though this level of naivety is rare (I hope), I have actually heard someone complaining about hunting, telling people they should get their meat from the grocery store where no animal lives were taken.
There are several benefits to hunting. It provides a cheaper, and usually healthier, grade of meat (fewer chemicals, hormones, etc); it allows for animals to live their lives in their natural environment instead of contributing to the unhealthy factory farm industry (which is often under increased scrutiny for animal welfare violations, human health concerns, and environmental contamination); it allows people another activity to do outdoors, which can contribute both to their own fitness as well as giving them an opportunity to develop a connection with their world (read about Nature Deficit Disorder); it aids biologists in their wildlife management programs, which in turn aids the environment; it can give the hunter or their friends/family access to leather or even bones for crafts such as clothes making, bone handles for knives, or even furniture (yes, I’ve heard of someone making a set of porch chairs out of bones and leather).
Not all hunters have an appreciation for wildlife, but many do. The first conservationists were often hunters, as are many wildlife and conservation biologists today. Indigenous tribes often hunt to keep a part of their culture, as well as to feed themselves in the face of poverty. The various hunting practices go back to the beginning of humanity and back still further; it is something the lion and the wolf and the shark all partake in. It has ecological value, but it can also devastate populations, bringing them to the point of extinction. This is why so many places, both on the national and state level, have come up with wildlife management practices, of which hunting is often a part.