Most research on climate change impacts on global biodiversity lacks the resolution to detect changes in species abundance and is limited to temperate ecosystems. This limits our understanding of global responses in species abundance—a determinant of extinction risk and ecosystem function and services—to climate change, including in the highly biodiverse tropics. We address this knowledge gap by quantifying the abundance response of waterbirds, an indicator taxon of wetland biodiversity, to climate change at 6,822 sites between 55° S and 64° N. Using 1,303,651 count records of 390 species, we show that with temperature increase, the abundance of species and populations decreased at lower latitudes, particularly in the tropics, but increased at higher latitudes. These contrasting latitudinal responses indicate potential global-scale poleward shifts of species abundance under climate change. The negative responses to temperature increase in tropical species are of conservation concern, as they are often also threatened by other anthropogenic factors.

关于气候变化对全球生物多样性影响的大多数研究缺乏检测物种丰度变化的分辨率，并且仅限于温带生态系统。这限制了我们对物种丰富度（灭绝风险以及生态系统功能和服务的决定因素）对气候变化（包括在高度生物多样性的热带地区）的全球响应的理解。我们通过量化水鸟（湿地生物多样性的一个指标分类）在55°S和64°N之间的6,822个站点对气候变化的丰度响应来解决这一知识鸿沟。我们使用390个物种的1,303,651个计数记录，表明随着温度的升高，在低纬度地区，特别是在热带地区，物种和种群的丰度下降，而在高纬度地区则增加。这些截然不同的纬度响应表明，在气候变化下，物种丰富度可能在全球范围内发生极向移位。热带物种对温度升高的负面反应值得保护，因为它们也经常受到其他人为因素的威胁。