An endangered species is a population of organisms which is facing a high risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters. The International Union for Conservation of Nature (IUCN) has calculated the percentage of endangered species. Many nations have laws offering protection to conservation reliant species: for example, forbidding hunting, restricting land development or creating preserves.
The conservation status of a species is an indicator of the likelihood of that endangered species becoming extinct. Many factors are taken into account when assessing the conservation status of a species, including statistics such as the number remaining, the overall increase or decrease in the population over time, breeding success rates, known threats, and so on. The IUCN Red List of Threatened Species is the best-known worldwide conservation status listing and ranking system. It has been estimated that over 40% of all living species on Earth are at risk of going extinct. Internationally, 199 countries have signed an accord agreeing to create Biodiversity Action Plans to protect endangered and other threatened species. In the United States this plan is usually called a species Recovery Plan.
In order to conserve the biodiversity of the planet, one must take into consideration the reasons why so many species are becoming endangered. "Habitat loss is the most widespread cause of species endangerment in the U.S., affecting 85% of imperiled species" (Wilcove & Master, 2008, p. 416). When an animals ecosystem is not maintained, they lose their home and are either forced to adapt to new surroundings or perish. Pollution is another factor that causes many species to become endangered. Also, over-exploitation, disease (Wilcove & Master, 2008, p. 416), and climate change (Kotiaho et al., 2005, p. 1963) have led to the endangerment of several species. Humans have an impact on the species and their environment. "As human use of resources, energy, and space intensified over the past few centuries, the diversity of life has been substantially diminished in most parts of the world" (Ishwaran & Erdelen, 2006, p. 179). Humans also set standards for which species they think should be saved and which species they find unimportant or undesirable. For example, the coquí frog, an invasive species in Hawaii, is so common there that its "nocturnal singing" reduces the value of homes and prevents hotels from using rooms near forests. Hawaiians have proposed eliminating the frog, and several wildlife managers want to release a pathogen to kill the frogs (Minteer & Collins, 2005, p. 333). The frog has decreased the value of homes and caused a loss of business for several hotels, so the Hawaiians decided it was acceptable to get rid of the group of coquí frog living near them. In another example where humans affected the welfare of a species, non-native mute swans started establishing themselves at Arrowhead Lake in Vermont. When the population of swans grew to eight birds, the Vermont Fish and Wildlife Department decided to take action. Two swans were eventually killed, angering animal welfare organizations and people living near the lake (Minteer & Collins, 2005, p. 333). Yet another example of the human impact in the lives of endangered species is that of the Prebles meadow jumping mouse. Research has shown that the mouse is not taxonomically different from the Bear Lodge meadow jumping mouse and the US Fish and Wildlife Service has proposed removing the Prebles mouse from the endangered species list based on this information (Minteer & Collins, 2006, p. 333).
It is the goal of conservationists to create and expand upon ways to preserve endangered species and maintain biodiversity. There are several ways in which one can aid in preserving the worlds species who are nearing extinction. One such way is obtaining more information on different groups of species, especially invertebrates, fungi, and marine organisms, where sufficient data is lacking. Another way to help preserve endangered species is to create a new professional society dedicated to ecological ethics. This could help ecologists make ethical decisions in their research and management of biodiversity. Also, creating more awareness on environmental ethics can help encourage species preservation. "Courses in ethics for students, and training programs for ecologists and biodiversity managers" all could create environmental awareness and prevent violations of ethics in research and management (Minteer & Collins, 2005, p. 336). One final way in which one can conserve endangered species is through federal agency investments and protection enacted by the federal government. "Ecologists have proposed biological corridors, biosphere reserves, ecosystem management, and ecoregional planning as approaches to integrate biodiversity conservation and socioeconomic development at increasingly larger spatial scales" (Ishwaran & Erdelen, 2006, p. 179). One example of a federal mandated conservation zone is the Northwest Hawaiian Islands Marine National Monument, the largest marine protected area in the world. The monument is essential to the preservation of underwater communities and overfished regions. Only researchers working in the area are permitted to fish, no corals may be removed, and the Department of Homeland Security will enforce restrictions on vessels passing through the waters via satellite imaging. The monument will serve as a home to an estimated seven thousand species, most of which cannot be found anywhere else in the world (Raloff, 2006, p. 92). This environmental monument demonstrates the fact that it is possible to create a safe environment for endangered species, as well as maintaining some of the worlds largest ecosystems.
Captive breeding is the process of breeding rare or endangered species in human controlled environments with restricted settings, such as wildlife preserves, zoos and other conservation facilities. Captive breeding is meant to save species from going extinct. It is supposed to stabilize the population of the species so it is no longer at risk for disappearing. This technique has been used with success for many species for some time, with probably the oldest known such instances of captive mating being attributed to menageries of European and Asian rulers, a case in point being the Pere Davids Deer. However, captive breeding techniques are usually difficult to implement for highly mobile species like some migratory birds (e.g. cranes) and fishes (e.g. Hilsa). Additionally, if the captive breeding population is too small, inbreeding may occur due to a reduced gene pool; this may lead to the population lacking immunity to diseases.
Whereas poaching causes substantial reductions in endangered animal populations, legal private farming for profit has the opposite effect. Legal private farming has caused substantial increases in the populations of both the southern black rhinoceros and the southern white rhinoceros. Dr Richard Emslie, a scientific officer at the IUCN, said of such programs, "Effective law enforcement has become much easier now that the animals are largely privately owned... We have been able to bring local communities into the conservation programmes. There are increasingly strong economic incentives attached to looking after rhinos rather than simply poaching: from eco-tourism or selling them on for a profit. So many owners are keeping them secure. The private sector has been key to helping our work” Conservation experts view the effect of Chinas turtle farming on the wild turtle populations of China and South-Eastern Asia—many of which are endangered—as "poorly understood. While they commend the gradual replacement of wild-caught turtles with farm-raised turtles in the marketplace (the percentage of farm-raised individuals in the "visible" trade grew from around 30% in 2000 to around 70% in 2007, they are concerned with the fact that a lot of wild animals are caught to provide farmers with breeding stock. As the conservation expert Peter Paul van Dijk noted, turtle farmers often believe in the superiority of wild-caught animals as the breeding stock, which may create an incentive for turtle hunters to seek and catch the very last remaining wild specimens of some endangered turtle species. In 2009, researchers in Australia managed for the first time to coax southern bluefin tuna to breed in landlocked tanks, opening up the possibility of using fish farming as a way to save the species from the problems of overfishing in the wild.