Declines Accelerate Across Key Metrics (Image Credits: Imgs.mongabay.com)
Migratory wildlife essential to global ecosystems continues to face mounting pressures, as a new United Nations interim assessment documents accelerated population drops across species safeguarded by international agreement.
Declines Accelerate Across Key Metrics
Nearly half of all populations of migratory species listed under the Convention on the Conservation of Migratory Species (CMS) now show decreasing trends, marking a rise from 44 percent documented two years earlier.[1][2]
The interim report, an update ahead of the full 2030 assessment, analyzed recent IUCN Red List data for nearly 1,200 protected species. It found 592 populations declining, with 24 percent of species now globally threatened with extinction, up from 22 percent.[1] Among 386 re-assessed species, 26 shifted to higher risk categories, including 18 migratory shorebirds.
Shorebirds in flyways like the East Asian-Australasian and East Atlantic suffered pronounced losses, driven by long-term habitat pressures. The report highlighted that many species previously deemed stable have revealed downward trajectories upon deeper analysis.
Habitat Loss Severely Fragments Migration Corridors
Development and infrastructure increasingly block vital pathways for species traversing continents and oceans. Roads, fences, railways, and dams have reduced connectivity for herds like the Mongolian gazelle and Bathurst tundra caribou, whose numbers plummeted from 450,000 in 1986 to just 6,240 by 2021.[1]
Agriculture, mining, and urban expansion degrade stopover sites critical for refueling during long journeys. Blue wildebeest in the Mara-Loita region lost 75 percent of their population since the late 1970s due to land-use changes. Freshwater fish populations declined by an average of 81 percent globally between 1970 and 2020, hampered by barriers and pollution.[3]
| Threatened Group | Key Impacts |
|---|---|
| Migratory shorebirds | Habitat loss at stopovers; 18 species upshifted in risk |
| Marine species (sharks/rays) | Overfishing; populations halved since 1970 |
| Terrestrial mammals | Infrastructure barriers; e.g., caribou decline |
Avian Influenza Adds Urgent Layer of Risk
Highly pathogenic avian influenza (HPAI H5N1) has infected 598 bird species and 102 mammals as of late 2025, triggering mass die-offs that compound existing stresses. Peruvian pelicans suffered around 20,000 deaths in 2023, while 1,500 to 1,700 hooded cranes perished in East Asia.[1]
Species like critically endangered African penguins, vulnerable hooded and red-crowned cranes, and Dalmatian pelicans faced heavy losses. Kelly Malsch, the report’s lead author from the UN Environment Programme, noted that HPAI particularly endangers long-lived migrants sensitive to added mortality. The disease disrupts ecological roles, from pest control to nutrient cycling.
Conservation Wins Point to Paths Forward
Despite the grim trends, targeted efforts yielded recoveries for select species. The scimitar-horned oryx rebounded to nearly 575 individuals in Chad following 2016 reintroductions, shifting from extinct-in-the-wild to endangered status. Saiga antelope populations stabilized after disease outbreaks in the 2010s through anti-poaching and habitat measures.[1][2]
CMS Executive Secretary Amy Fraenkel emphasized corridors as a core solution, urging networks of protected areas across borders for birds and ocean species. The Serengeti-Masai Mara ecosystem sustains 2.5 million migrants annually via such linkages. At the upcoming CMS Conference of the Parties in Brazil, delegates will consider listing 42 additional species.
- Map precise migration routes for planning.
- Secure transboundary habitat connections.
- Implement science-based fisheries and hunting limits.
- Monitor and mitigate disease outbreaks.
- Expand protected networks for aerial and marine travelers.
- 49% decline rate signals urgent need for action.
- HPAI exacerbates habitat and exploitation threats.
- Success stories prove conservation delivers results.
This interim report underscores that while challenges intensify, coordinated global steps can reverse declines and safeguard migratory species vital to planetary health. What steps should governments prioritize next? Share your thoughts in the comments.
