美国康奈尔大学Kenneth V. Rosenberg研究团队近期报道了北美鸟类的减少。2019年9月19日，《科学》在线发表了这项成果。

使用多个独立的监测网络，研究人员报告了48年来大部分北美鸟类的群体损失，包括曾经常见的物种和大多数生物群落。范围广泛的群体轨迹和规模估计的整合表明净损失接近30亿只鸟，占1970年丰度的29％。大陆范围内的天气雷达网络也显示，近10年来候鸟的生物量通过量同样急剧下降。这种鸟类丰度的丧失标志着迫切需要解决威胁，以避免未来的禽流感崩溃以及相关的生态系统完整性、功能和维护的丧失。

据了解，物种灭绝决定了全球生物多样性危机，但灭绝始于个体数量的减少，这可能导致生态系统的组成和功能变化。

附：英文原文

Title: Decline of the North American avifauna

Author: Kenneth V. Rosenberg, Adriaan M. Dokter, Peter J. Blancher, John R. Sauer, Adam C. Smith, Paul A. Smith, Jessica C. Stanton, Arvind Panjabi, Laura Helft, Michael Parr, Peter P. Marra

Issue&Volume: 2019/09/19

Abstract: Species extinctions have defined the global biodiversity crisis, but extinction begins with loss in abundance of individuals that can result in compositional and functional changes of ecosystems. Using multiple and independent monitoring networks, we report population losses across much of the North American avifauna over 48 years, including once common species and from most biomes. Integration of range-wide population trajectories and size estimates indicates a net loss approaching 3 billion birds, or 29% of 1970 abundance. A continent-wide weather radar network also reveals a similarly steep decline in biomass passage of migrating birds over a recent 10-year period. This loss of bird abundance signals an urgent need to address threats to avert future avifaunal collapse and associated loss of ecosystem integrity, function and services.

DOI: 10.1126/science.aaw1313

Source: https://science.sciencemag.org/content/early/2019/09/18/science.aaw1313