"Study using citizen data finds three-quarters of nearly 500 species in decline, with steepest trend in areas where they once thrived"
"Bird populations across North America are falling most quickly in areas where they are most abundant, according to new research, prompting fears of ecological collapse in previously protected areas.
Analysis of nearly 500 bird species across North America has found that three-quarters are declining across their ranges, with two-thirds of the total shrinking significantly.
The study, published in the journal Science, indicates that former strongholds for bird species are no longer safe, particularly in grasslands, drylands and the Arctic.
In one of the most ambitious uses of citizen science data so far, scientists at Princeton University used observations from eBird, a popular application used by birdwatchers to record sightings, to model changes between 2007 and 2021. The granularity of the data allowed researchers to track the rate of change in 27 sq km (10 sq miles) segments across North America, showing dramatic declines in areas where less than two decades ago bird species had thrived."
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