But in North America, we've seen a staggering loss of birds. A 2019 study led by the Cornell Lab of Ornithology found that there are 3 billion fewer breeding birds than in 1970. To put that into context: we've lost roughly one in four birds over the course of my parents' lifetime. More than 90% of these losses are of common birds, like sparrows, blackbirds and finches.
Birds can serve as indicator species, which are species that help us understand how healthy an ecosystem is. "If we're seeing them decline, then we know something is wrong with our environment and that should concern us, because our health is tied up in the same shared environment," says Miyoko Chu, the director of communications at the Cornell Lab of Ornithology.