Peter Marra, dean of the Earth Commons Institute at Georgetown University, said on Apr. 22 that bird populations in North America have declined by about three billion since 1970, representing roughly a third of the continent’s total. Marra co-authored a 2019 study highlighting this trend and noted that recent research shows the rate of decline is accelerating.
The decline in bird populations has raised concerns among scientists and conservationists because birds play important roles in ecosystems as pollinators, seed dispersers, and indicators of environmental health. Marra said that habitat loss from development and agriculture is a major factor driving these declines. “Birds can’t adapt overnight to living in a totally different place or a new habitat. All birds are somewhat specialized for where they live,” Marra said. “When we change those habitats to something less natural, you don’t typically get many species in those areas.”
Marra emphasized the interconnectedness between humans and their environment, stating, “All these ecosystems, humans are intricately tied to, despite the fact that we want to believe we’re separate from our environment.” He added that declines have also been influenced by invasive species, contaminants, overharvesting by humans, and climate change.
To address these issues, Marra helped found Road to Recovery at Georgetown University in 2020—a program aimed at targeted interventions for more than 100 bird species nearing endangered status. He suggested policy changes such as incentivizing farmers not to cut fields during nesting seasons or flooding rice fields during migration periods could help support vulnerable species.
Marra also encouraged individual actions like keeping cats indoors—citing estimates that cats kill between 1.2 and 4 billion birds annually—and planting native vegetation while avoiding pesticides. He recommended supporting agricultural products grown using bird-friendly practices.
“Nature is resilient,” Marra said. “If given a chance, we can figure out exactly how to minimize our impact on birds… They will come back but they need to be given a chance.”
