Humans have always made use of animals and plants to meet their needs. Whether for food and firewood, or clothing and furniture, people have killed animals and cut down trees. When this is done in ways that don’t threaten the future of a wild species, it is not currently seen as a crime.
However, in some cases, humans have taken more animals or plants of a particular species than can be sustained. Some species are being driven to extinction because people are killing them at such a rapid rate. Over the last 30 years or so there has been growing world-wide concern that trade in endangered species should be controlled. When people hunt endangered animals illegally (called poaching) or when they buy and sell products made from endangered species, this is now considered a wildlife crime.