Role of wetlands in the Pampas of Argentina in global shorebird conservation.

Less than 10% of migratory bird species worldwide benefit from adequate protected area coverage throughout their annual cycles. This increases their vulnerability and exacerbates the global biodiversity crisis. The ongoing decline of shorebird populations, 60% of which are migratory, suggests critical gaps in current conservation strategies. One such gap is the spatial bias in surveys and monitoring efforts. Such efforts are heavily concentrated in the Global North, leaving regions in the Global South underrepresented. We assessed the importance of a vast inland region in southern South America, the Inland Pampas of Argentina, for shorebird conservation, as it supports thousands of wetlands but has been largely overlooked in shorebird research and conservation. We conducted shorebird counts in 134 wetlands across the region in January and June of 2021, 2022, and 2023. Seventeen species were recorded, including 3 of global conservation concern: white-rumped sandpiper (Calidris fuscicollis), Hudsonian godwit (Limosa haemastica), and lesser yellowlegs (Tringa flavipes). Shorebird abundance peaked in January (maximum number of approximately 30,000 individuals) and was dominated by Nearctic migrants. In contrast, June assemblages were dominated by Neotropical species and Hudsonian godwits, indicating the region serves as an important oversummering site for the latter. In June, there was also an influx of godwits from other nonbreeding areas. Three wetlands had notably high numbers of shorebirds, including populations that met criteria for international importance. Because of the abundances we found, our results underscore the urgent need to expand research efforts to identify other high-priority areas for shorebirds in the Global South. Neglecting these regions would bias global population assessments and risk omitting critical habitats from national and international conservation frameworks. Addressing these data gaps is essential not only for updating global priorities but also for promoting more inclusive and geographically balanced approaches to migratory shorebird conservation. The complete Spanish version of the manuscript is available as Supplemental Material (S2).