What criteria are used to classify species as endangered?

Species are classified as endangered based on a range of criteria that reflect their conservation status. The correct choice emphasizes three critical factors: population size, rate of decline, and threats.

Population size is vital because a small number of individuals can make species more vulnerable to extinction, especially if their numbers are critically low. This means that if a species has very few members left, it is considered more at risk.

The rate of decline provides insight into how quickly a species is losing its population, which can signal whether the situation is worsening and if immediate conservation efforts are needed. A rapid decrease in population indicates that the species is in peril and requires urgent protection measures.

Lastly, the assessment of threats involves understanding the various factors negatively impacting a species, such as habitat loss, climate change, poaching, pollution, or invasive species. Knowing the specific threats helps conservationists develop targeted strategies to protect the species.

Together, these three criteria create a comprehensive picture of a species' status and the urgency of conservation actions needed to ensure its survival. This multifaceted approach explains why the classification of endangered species relies on a combination of these factors rather than focusing on just one or two aspects.