Hunting has become one of the main reasons behind the extinction of mammals and other animal species.

During the 19th century, passenger pigeons became officially extinct due to massive hunting in North America. Ecologists conclude that around 301 species (including 26 bats, 126 primates and 65 ungulates like wild pigs and deer) are facing extinction.

A recent study revealed that a "substantial number of mammals" are likely to disappear due to hunting. Lead author William Ripple said that his study in Africa involving lions helped to raise awareness about the issue. He revealed that the preys that serve as predators' food are not enough.

Ripple, who is an ecologist with Oregon State University, revealed that humans and large carnivores are competitors for bushmeat. To elucidate the issue, Ripple and his team assessed the Red List of Threatened Species which includes the names of threatened and endangered floras and faunae of the world. The study concentrated on 1,169 threatened land mammals to identify the animal species that are most at risk from hunting for the purpose of meat, pet trade, or medicine.

Ripple noted that "a lot of people think the loss or degradation of habitat is the big threat to wild animals, but here it shows there is a major threat from direct exploitation by humans."

A quarter of the mammals included in the study have been hunted to the brink of extinction by humans. Land animals like hippos and rhinos are particularly vulnerable due to their long gestation periods and small population count. The population of other species such as sloth bears, gaurs, bearded pigs, and Bactrian camels is also declining due hunting.

E.J. Milner-Gulland of the University of Oxford stated that past hunting evaluations only covered high-profile animals like tigers and elephants and set aside rodents and other less attractive animals. The study stressed that the loss of 301 species might result in an imbalance in the ecosystems.

The threatened animals include those which regulate the population of plant eaters and those that help in seed dispersal. The Center for International Forestry Research approximated that six million tonnes of bushmeat were hunted in 2011.

Professor David Mac Donald clarified that people should know how to "distinguish between those people who have no choice but to eat bushmeat and what is to be done for them, and people living in towns who have a nostalgic memory for the time when they lived on bushmeat, but no longer need to, so it is a luxury."

The research emphasized that to address the issue of over-hunting, stricter legal protection is necessary.