Are there more endangered bird species than we think?

Hundreds of bird species around the world are endangered even though they’re not classified as such, according to a new study. Using geographical data, scientists analyzed the habitats of certain birds and concluded that the International Union for Conservation of Nature’s Red List — the definitive guide to endangered animals — underestimates the risk for 210 bird species. Red List officials disagree with the findings, saying that the new calculations are wrong and the st