Sustainable hunting is a conservation-based hunting approach that does not reduce the density[1] of the game animal being hunted via the adherence to hunting limits.[2] Sustainable hunting is a method of hunting that focuses on not degrading the environment and using fees related to hunting for conservation purposes to instead protect and help the environment flourish.[3] This concept is supposed to be a more sustainable and less invasive form of hunting as it aims to preserve or even improve the environment where unregulated hunting can destroy and even cause species to go extinct when left unchecked.[4] In order for hunting to be sustainable, hunting laws and limits[3] must be followed. Species that are vulnerable or endangered must be protected,[3] as taking from their population can be detrimental. Once the level of removal reaches a level higher than the population can reproduce,[1] then the extraction of species in that area is no longer sustainable as, over time, the numbers will dwindle. Certain precautions need to be taken in regard to species that do not reproduce as fast; one such precaution is allowing the animal to be hunted once it has reached an age where it can no longer reproduce.[1] Utilizing hunting and its associated fees to generate conservation revenue has proven successful in the past.[3] Still, due to limited data and issues around ethics, current efforts and other challenges prevent the growth of sustainable hunting as a model. Some troubles with compiling accurate research include subpopulations of species intermixing with other populations and allowing the species to recover[1] where if it were left isolated, its rate of decline would have been too high to be sustained. Methods for sustainable hunting vary, but researchers are looking to find the maximum level of game[1] that can be taken while still being sustainable to reap the most benefits per season.