Nearly half of world’s migratory bird species in decline, report warns

Nearly half of the world’s migratory bird species are experiencing population declines, while one in nine is threatened with extinction, according to a global assessment released Friday.

BirdLife International’s State of the World’s Birds 2026 report found that 45% of the 1,843 migratory species assessed had declining global populations. Thirty percent were considered stable, 14% were increasing and the trends of the remaining 11% were unknown.

The sixth edition of the report, which focuses on migratory species and the routes they follow, combines BirdLife’s data with findings from broader scientific research.

It identified 200 migratory species, or 11%, as threatened with extinction. Of those, 32 were classified as critically endangered, 57 as endangered and 111 as vulnerable.

A further 111 species were listed as near threatened, meaning around 17% of all migratory birds are considered to be of significant conservation concern.

The report found particularly severe declines among birds that depend on marine and coastal wetlands. Some 54% of migratory shorebird species and 49% of migratory seabirds are declining, as are between 47% and 51% of species associated with marine habitats, forests and coastal wetlands.

The East Asian-Australasian Flyway had the highest proportion of declining species among the four major land-based flyway systems, at 53%. Half of the species using the world’s six marine flyways were also in decline.

Regional monitoring indicated that long-distance migratory birds traveling between Europe and Africa had declined by around 35% since 1980. In North America, 419 migratory species experienced a net loss of approximately 2.5 billion birds between 1970 and 2017, according to studies cited in the report.

Migratory shorebirds have been among the most severely affected. In North America, 26 of the 28 shorebird species monitored between 1980 and 2019 experienced declines, with more than half losing over 50% of their populations.

The slender-billed curlew, a migratory shorebird last reliably recorded in Morocco in 1995, has been declared extinct. Researchers described it as the first known global bird extinction of a species native to mainland Europe, North Africa and West Asia.

Worldwide, seven migratory bird species have been confirmed or are suspected to have become extinct over the past 150 years.

The assessment showed that the extinction risk facing migratory birds continues to increase. A total of 102 species moved into a higher-risk category because of a genuine deterioration in their status, compared with 34 that moved to a lower risk category following improvements.

Human activity was responsible for nearly all the principal pressures identified in the report. Invasive species and diseases affected 139 threatened migratory species, while agriculture and climate change each affected 103.

Hunting and trapping affected 99 threatened species, followed by pollution at 96, urban development at 71, human disturbance at 65, fisheries at 62, energy infrastructure at 55 and logging at 39.

“Migratory birds are sentinels, and their declines reveal growing pressure on the natural systems that sustain us,” said Stuart Butchart, BirdLife International’s chief scientist.

Butchart said coordinated conservation efforts had prevented extinctions and helped some populations recover, but action needed to be implemented across entire flyways rather than in individual countries.

Flyways are migration corridors connecting birds’ breeding, feeding and wintering grounds across countries and continents. The loss of a single important wetland, forest or coastal resting site can therefore affect populations across a species’ entire range.

The report called for stronger international cooperation to protect and restore habitats, prevent illegal killing, reduce seabird deaths caused by fishing, control invasive species and make agriculture, forestry and infrastructure safer for wildlife.

It warned that progress toward biodiversity targets adopted by 196 countries for 2030 remained “far too slow.”

The report was launched during the Global Flyways Summit in Nairobi, Kenya, where governments, conservation groups, scientists and financial institutions adopted the Nairobi Flyways Declaration, pledging greater cooperation along migratory routes.

The declaration was accompanied by plans involving the Asian Development Bank, the Development Bank of Latin America and the Caribbean, and the World Bank to integrate flyway protection into development financing and mobilize about $6 billion for habitat conservation and restoration.