How do scientists count species populations?

Scientists count species populations using various methods depending on the species and habitat. Common techniques include direct observation, capture-recapture methods, and sampling. For example, they might mark a portion of the population, release them, and later recapture to estimate total numbers based on the ratio of marked to unmarked individuals. Additionally, remote sensing and environmental DNA (eDNA) analysis are increasingly used to estimate populations in hard-to-reach areas.