Grassland bird population declines at three Breeding Bird Survey spatial scales in contrast to a large native prairie

Grassland biomes in North America are threatened by agricultural intensification with implications for grassland associated bird populations via habitat loss, alteration, pesticide use and declining landscape heterogeneity. Despite decades of conservation concern, steep declines of North American grassland bird populations continue. Key to optimizing conservation effort is understanding how land-use practices, such as agriculture, across the annual cycle affects population status. Determining the relative influence of impacts on grassland bird declines is difficult given that the most robust estimates of population trends, the North American Breeding Bird Survey (BBS), are from surveys throughout agriculturally dominated regions. Our goal was to explore whether agriculture during the breeding season is a major driver of grassland bird declines. We derived trends for 16 grassland bird species spanning 23 years (1994-2016) at a large (459 km2), native prairie site, Suffield National Wildl...

北美草原生物群系（Grassland biomes）正遭受农业集约化的威胁，其通过栖息地丧失、生境改造、农药施用以及景观异质性下降等途径，对依附草原生存的鸟类种群造成负面影响。尽管数十年来保护学界始终对此予以关注，但北美草原鸟类种群的大幅衰退仍在持续。优化保护工作的核心在于厘清：全年周期内的土地利用实践（如农业生产活动）如何作用于种群现状。由于当前最可靠的种群趋势估算数据——北美繁殖鸟类调查（North American Breeding Bird Survey, BBS）——均来自农业主导区域的调查结果，因此难以明确各类影响因素对草原鸟类种群衰退的相对影响力。本研究旨在探究繁殖季的农业活动是否为草原鸟类种群衰退的主要驱动因素。我们在一处面积达459平方千米的原生草原站点——萨菲尔德国家野生动物保护区（Suffield National Wildlife Area）——针对16种草原鸟类，获取了1994年至2016年共计23年的种群趋势数据。