Indigenous Peoples and locals report a drastic decline in bird size across three continents

> The analysis reveals a consistent pattern: large-bodied bird species have progressively disappeared from local environments, being replaced by smaller-bodied species. Whereas in the 1940s the mean body mass of reported bird species exceeded 1,500 grams, by the 2020s the average stands at around 535 grams. Overall, statistical models point to a decline of approximately 72% in the mean body mass of the bird assemblages observed by these communities over eight decades. > The study also underscores that the global avian extinction crisis, widely documented in scientific literature, is equally perceptible in the collective memory of communities with long-term, place-based connections to their territories. Rather than treating Indigenous and local knowledge as merely complementary data, "we advocate for a respectful and equitable dialogue between scientific and Indigenous knowledge systems, recognizing their inherent value and their potential to strengthen biodiversity policy and conservation practice," says Dr. Fernández-Llamazares.