It’s tough to make it as a bird in the modern world—even tougher than scientists previously thought.
According to a study released in September, the bird population of the U.S. and Canada has declined 30% since 1970.
The study was published in the journal Science and was conducted by researchers at seven different research organizations in the U.S. and Canada.
Although many bird species have known to be particularly vulnerable to the pressures of their environment, this study shows that even common species such as robins, blue jays blackbirds have declined. Overall, there are 2.9 million fewer birds in the sky than there were 50 years ago, across every type of habitat.
Grassland birds have suffered one of the steepest declines, according to the study. The loss of grassland habitat to agriculture and development is likely a large component, according to the researchers. Boreal forest birds, which can be found in the remote northern regions of Minnesota, have declined by 33%. These include iconic Minnesota Northwoods species such as Canada jays, white-throated sparrows and dark-eyed juncos.
Pesticides also likely play a role in the decline. Another recent study showed that the neonicotinoids used in agriculture make it difficult for birds to gain enough bodyweight for migration.
Scientists compared their results to radar records, which show bird populations during migration. The population decline they observed corresponded with radar observations, showing a decline of 14% of the bird population since 2007.
The Cornell Lab of Ornithology quoted one of the study’s authors, biostatistician Adam Smith of Environment and Climate Change Canada.
“It’s really a wake-up call for the importance of moving beyond just a single species, endangered species conservation framework,” he said. “We rescued the trumpeter swan and the peregrine falcon, and we should be proud and happy about those successes. But we’re at a stage where, given these extreme declines in so many species, we need to move beyond that framework.”
The decline has happened gradually enough that many people might not have noticed it happening. Even popular feeder birds such as the Baltimore oriole has diminished in population by about 30%.
However, despite the worrisome findings of rapid decline, the study also found that some bird species are thriving. Conservation efforts likely paved the way for waterfowl and upland game birds such as wild turkey.
Raptor conservation programs, initiated after the birds were nearly decimated by the pesticide DDT in the 1960s, have helped to increase their populations by 200%.
The study was completed with the assistance of thousands of citizen-science observations from amateur birdwatchers, compiled over decades. This data included results from the long record of Christmas Bird Counts, which take place in local communities around Minnesota and all of North America every winter.
Though the numbers for most bird species seem grim, research leader Kenneth Roseburg told the Cornell Lab of Ornithology that there’s still room for hope to recover the declining species, but similar conservation action is needed quickly.
“I don’t think any of these really major declines are hopeless at this point,” he said. “But that may not be true 10 years from now.”