The study, which was carried out by scientists at seven research institutions in the US and Canada, found that the total population of more than 300 bird species in the US and Canada has declined by almost 29% over the past 50 years. With birds being a vital part of the food chain and the world’s ecosystem, a decrease in their abundance suggests that the Earth’s ecosystem is in trouble.
“Multiple, independent lines of evidence show a massive reduction in the abundance of birds,” said Ken Rosenberg, the study’s lead author and a senior scientist at the Cornell Lab of Ornithology and American Bird Conservancy, according to the New York Post. “We expected to see continuing declines of threatened species. But for the first time, the results also showed pervasive losses among common birds across all habitats, including backyard birds.”
Grassland birds, in particular, have experienced a 53% reduction in population, while shorebirds have lost more than a third of their population.
“These data are consistent with what we’re seeing elsewhere with other taxa showing massive declines, including insects and amphibians,” coauthor Peter Marra, director of the Georgetown Environment Initiative at Georgetown University, is quoted as saying by USA Today. “It’s imperative to address immediate and ongoing threats, both because the domino effects can lead to the decay of ecosystems that humans depend on for our own health and livelihoods — and because people all over the world cherish birds in their own right. Can you imagine a world without birdsong?”
Although the study did not evaluate the reasons behind the population changes, it did note that the declines in the US and Canada correspond to a reduction in birds in other parts of the world and may therefore be related to habitat degradation and urbanization.
On a positive note, there are steps that can be taken to prevent additional bird population declines, according to the researchers. Keeping cats indoors, avoiding the use of pesticides and installing screens on windows to prevent birds from flying into buildings are all examples of measures that can conserve bird populations. In addition, policy decisions can be made to fund bird conservation programs.