An interim report which provides an update to the landmark State of the World’s Migratory Species (2024) warns that 49% of migratory species populations conserved by the global UN treaty are declining, (5% more in just two years), and 24% of species face extinction (2% more).
The new warnings are set to be presented to the 15th Meeting of the Conference of the Parties to the Convention on the Conservation of Migratory Species of Wild Animals (CMS COP15), a legally binding treaty of the United Nations, in Campo Grande, Brazil, from March 23 to 29, 2026.
The week-long COP is one of the most important global meetings for wildlife conservation. With high-level political attention from host-country Brazil, the meeting is set to tackle an ambitious set of actions addressing a vital aspect of the global biodiversity crisis.
Billions of individual aquatic, avian, and terrestrial wild animals migrate across lands, rivers, oceans and skies. They are essential to the well-functioning of nature and to human well-being, pollinating plants, transporting nutrients, regulating ecosystems, controlling pests, storing carbon and sustaining livelihoods and cultures worldwide.
Their survival depends on coordinated action across the full length of their migratory routes, which can cross multiple national borders and even continents.
Developed for CMS by the UN Environment Programme World Conservation Monitoring Centre (UNEP-WCMC) and other contributors, the interim report tracks significant changes in the conservation status of migratory species and highlights emerging trends to provide new information focusing on:
- Recent significant changes in the conservation status of species listed under the Convention on Migratory Species (CMS-listed) since the 2024 baseline, based on data from the IUCN Red List of Threatened Species.
- Newly reported population trends and changes in extinction risk documented in the scientific literature.
The report also underlines encouraging developments:
- Advances in mapping of migratory pathways to inform decision-making. Initiatives to map migrations are gathering momentum. This includes those spotlighted in the report – the Global Initiative on Ungulate Migration (GIUM), the Migratory Connectivity in the Ocean (MiCO) system, and BirdLife International’s work to identify and map six major marine flyways.
- Progress in identifying and safeguarding important habitats and migratory corridors.
- Recovery of some species through coordinated action.
Other key findings:
- 26 CMS-listed species, including 18 migratory shorebirds, have moved to higher extinction risk categories.
- Seven CMS-listed species have improved, including the saiga antelope, scimitar-horned oryx, and Mediterranean monk seal.
- 9,372 Key Biodiversity Areas (KBAs) important for CMS-listed species have been identified.
- 47% of the area covered by KBAs is not covered by protected and conserved areas.
- Progress has been made on filling gaps in knowledge on important habitats and migratory routes for sharks/rays and marine mammals, and new initiatives will identify areas for marine turtles.
- Despite some important successes, key indicators – such as the overall proportion of CMS-listed species with decreasing populations – are heading in the wrong direction.
The new report is based on the latest available data, including significant changes in conservation status, newly reported population trends, and recent progress in identifying and protecting critical habitats and migratory pathways.
This focused update provides Parties with the latest available evidence ahead of COP15 deliberations, helping to identify priority areas for action in advance of the next full report in 2029 at COP16.
Overexploitation, and habitat loss and fragmentation, are the two greatest threats to migratory species worldwide, notes CMS Executive Secretary, Amy Fraenkel.
“The first global report was a wake-up call,” she said. “This interim update shows that the alarm is still sounding. Some species are responding to concerted conservation action, but too many continue to face mounting pressures across their migratory routes. We must respond to this evidence with coordinated and effective international action.”
The report underscores the need for action to improve the status of all migratory species listed on the Convention, but most urgently for the species listed on CMS Appendix I, where migratory species in danger of extinction throughout all or a significant portion of their range, are listed.
These 188 Appendix I species include terrestrial mammals (28), aquatic mammals (23), birds (103), reptiles (8), and fish (26).
Parties that are Range States to Appendix I-listed species are required to provide strict protection, including the prohibition of taking (such as hunting or capturing), protecting and restoring important habitats, and addressing obstacles that impede the species’ migration.
Among other measures, a Global Initiative on Taking of Migratory Species (GTI) is expected to be launched at COP15. The new CMS-initiated initiative is designed to help governments, experts and local communities to ensure that any taking of migratory species is legal, sustainable and safe. It focuses on new findings that the threat of taking for domestic use is far greater than international trade.
“If we intervene only at the point of crisis, we risk acting too late,” said Fraenkel. “By strengthening governance, monitoring, legislation and community engagement upstream, we can reduce pressure on these remarkable animals and put them on the path to lasting recovery.”
Building on a landmark baseline
The 2024 State of the World’s Migratory Species report marked the first comprehensive global assessment of migratory animals, covering the 1,189 species listed at that time in CMS Appendices I and II and its analysis is linked to over 3,000 additional migratory species.
It found that:
- 70 CMS-listed species had become more endangered over the previous three decades, compared to just 14 that improved in status.
- Migratory fish populations had declined by 90% on average since the 1970s and 97% of CMS-listed migratory fish species face extinction.
- More than half of Key Biodiversity Areas important for CMS-listed species lacked protected status.
The interim report update ensures that governments at CMS COP15 have the most current scientific picture before them.
“We have a baseline. We have better tools. And we have growing public awareness,” Fraenkel said. “The question before governments at COP15 is straightforward: will we match this knowledge with the political will and investment needed to secure the future of the world’s migratory species?”