What term is used for species whose population is reduced to the point of nearing extinction?

The term for species whose population is reduced to the point of nearing extinction is "endangered species." This designation is used to identify species that are at a critical risk of disappearing from their natural habitats due to factors such as habitat loss, overexploitation, pollution, and climate change. Endangered species are often given special protections under law to help conserve their populations and restore their natural habitats. This status indicates an immediate threat to the species' survival and often comes with action plans for protection and recovery efforts.

In contrast, "vulnerable species" refers to those at risk but not as severely threatened as endangered species, while "threatened species" includes those that are likely to become endangered soon. "Protected species" is a more general term that can apply to various species under various conservation laws without specifically indicating their risk of extinction. Each of these terms reflects different levels of risk and conservation measures, but "endangered species" specifically identifies those populations that are on the brink of extinction.