Reading the morning snail mail used to be the go-to way for conservationists to learn which birds could soon be extinct. Stuart Butchart remembers how scientists in remote enclaves would post their dispatches to BirdLife International, the nearly century-old consortium of avian-conservation groups (including the 吃瓜黑料). The field summaries and expedition journals catalogued the health of birds and their habitat and helped inform endangered-species lists as recently as the 1980s. But the massive library had its gaps, says Butchart, BirdLife’s chief scientist. And so in the past decade, researchers have been turning to artificial, off-the-ground intelligence to plug those holes. One means of judging a species’ extinction risk is to look at how its range transforms over time. But with landscapes constantly shifting due to climate change and other human threats, experts in the field struggle to stay up-to-date. Finite resources, such as money, hours, and...