What Does
Threatened Species Mean?
A threatened species is any species that is at risk of endangerment. Without corrective measures, these species are likely to become extinct in the forseeable future.
Safeopedia Explains Threatened Species
The International Union for the Conservation of Nature (ICUN) divides threatened species into three categories:
- Vulnerable species
- Endangered species
- Critically endangered species
The National Wildlife Federation, on the other hand, only distinguishes between threatened and endangered species.
What Causes Species to Become Threatened?
Over 1,300 plant and animal species in the U.S. are considered threatened or endangered. As human activities expand, they threaten the habitat of various species and, as a result, their continued existence. Other factors like pollution, overharvesting, and the introduction of non-native species can also put species at risk.
Broadly speaking, the two main reasons for species endangerment are a loss of habitat and a loss of genetic variation.
Loss of Habitat
Housing developments, industrial expansion, and agricultural activities all contribute to the loss of species habitats. This can harm species directly by displacing them and eliminating the spaces in which they dwell. In other cases, the elimination or reduction of a species can affect those in surrounding areas who depend on it for sustenance.
Loss of Genetic Variation
A species' genetic diversity allows it to better adapt to changes in its environment. When a disease strikes the population, for instance, this variation increases the odds that a subset of it can resist it and continue to thrive.
As popualtions decline, however, genetic variation tends to dwindle. Individuals in shrinking populations are more likely to breed with closely related members, making the genetic makeup of the population even more homogeneous.
IUCN Red List Categories
The International Union for Conservation of Nature (IUCN) Red List Categories rates the extinction risk of species. These threat categories, in descending order of threat, are:
- Extinct or extinct in the wild
- Critically endangered, endangered, and vulnerable (species threatened with global extinction)
- Near threatened (species close to threatened thresholds, or would be without ongoing conservation measures)
- Least concern (lower risk of extinction)
- Data deficient (insufficient data)
Threatened and Endangered Species Program
The Bureau of Land Management's (BLM) Threatened and Endangered Species program manages all threatened, endangered, and designated Bureau Sensitive species on public lands. Under the Endangered Species Act (ESA), the organization is required to implement conservation programs to not only recover species under threat, but also the habitats they rely on for sustenance, shelter, and survival.
The BLM is also required to ensure that authorized activities do not cause further harm to the species or their habitats. To minimize potential adverse effects to any activities carried out by the BLM, the organization consults with the U.S. Fish and Wildlife Service and the National Marine Fisheries Service.