Populations of animals or plants that are at risk of becoming extinct are called endangered or threatened species. They show reduced numbers resulting from environmental change (such as global warming, pollution and habitat loss) or from increased predation by others animals. The danger of extinction is not only losing biodiversity; it may put an end to a pathway of evolution.
According to the International Union for Conservation of Nature (IUCN), in 2006, approximately 40% of all species, plants and animals were considered endangered. It does not mean that all these groups figure in threatened species lists and that they are legally protected. Without our knowing, there can be several species that will soon be wiped off the earth. Habitat loss, hunting and poaching, urbanization and grazing, all contribute to the threat faced by wildlife.
How do we know that any group is endangered? Is it only the low prevalence levels that contribute to this classification? The answer to this is no, because factors like overall increase/decrease in population within a specific time, breeding success rates and known threats are also considered. The IUCN Red List paints a very good picture of the wildlife that needs protection and their conservation status. The IUCN has an ambitious plan of evaluating the groups in this List for every 5-10 years.
We can further sub-divide the ‘endangered’ category, into the following:
1) Critically endangered – facing an immediate, very high risk of extinction i.e., Javan Rhino, Ivory-billed Woodpecker
2) Endangered- facing a high risk of extinction in the near future i.e., Blue Whale, Cheetah, Snow Leopard, Tiger
3) Vulnerable- facing a high risk of extinction in the medium term i.e., Lion, Wolverine
Some of the laws pertaining to threatened animals are rather controversial. One main concern about listings is the inclusion and the removal of groups. To illustrate this point, let’s say a population that numbers to less than 1000 is considered to be threatened. What if that number is currently 1001? Do we wait for two more deaths before trying to protect the animal? Is that fair? In the same manner, once a group is slowly regaining its numbers and coming out of its vulnerable state, when is it most appropriate to remove them from the endangered list? Scientists have not arrived at a consensus.
Another concern is that any animal that is tagged as endangered immediately becomes attractive and valuable in the eyes of poachers and collectors. In order to avoid losing their land to the government for the sake of conservation, private land owners may be reluctant to cooperate with protection laws. The news is not all discouraging. Around 19 species have been restored and more than 90% of listed species are reported to be on their way to recovery or a stable population dynamic.