With ongoing rapid urbanization, urban biodiversity conservation is becoming a primary issue for the maintenance of urban ecosystem functions, and given that birds play valuable ecosystem roles, their preservation is a matter of both ecological and social importance. Although it is generally considered that urban areas have low biodiversity and ecosystem value, these areas can serve as important wintering grounds for both resident and migratory birds. However, as comprehensive surveys of such biota are time- and resource-consuming, it would be useful to establish efficient conservation surrogates that could be used to identify areas of conservation importance. In this study, I evaluated the efficacy of raptor habitats as a conservation surrogate for high avian taxonomic and functional diversities in urban ecosystems in the wintering season. From December 2019 to February 2020 (wintering season), avian species that appeared within 500 m of 30 Northern Goshawk (Accipiter gentilis) breeding sites in eastern Kanagawa Prefecture, Japan, were investigated using point counts. I subsequently measured species richness and dendrogram-based functional diversity (FD) as indicators of avian taxonomic diversity and the ecosystem functions provided by birds, respectively, and performed the same procedures at 30 randomly selected points in areas similar to goshawk breeding habitats. Thereafter, using generalized linear models, I compared species richness and FD at sites with and without goshawk nests. I accordingly found that the presence of goshawk breeding sites is significantly positively associated with avian species richness and FD, explaining most of the variability in these data (species richness: 66.4 %, FD: 66.0 %). In conclusion, these findings indicate that goshawk breeding sites could be used as a conservation surrogate to identify and preserve habitat hotspots for wintering birds in urban ecosystems. These results can provide a basis for implementing appropriate conservation measures to maintain avian diversity in urban ecosystems.

随着持续的快速城市化，城市生物多样性保护已成为维持城市生态系统功能的首要问题，鉴于鸟类在生态系统中发挥着重要作用，因此鸟类的保护既具有生态意义，也具有社会意义。尽管通常认为城市地区的生物多样性和生态系统价值较低，但这些地区可以作为常驻鸟类和候鸟的重要越冬地。但是，由于对此类生物群进行全面调查既耗时又耗费资源，因此建立有效的保护替代品（可用于识别具有保护意义的领域）将很有用。在这项研究中，我评估了猛禽栖息地作为冬季生态系统中高鸟类生物分类学和功能多样性的保护替代品的功效。龙胆鹰嘴豆）利用点数调查了日本神奈川县东部的繁殖地。随后，我测量了物种丰富度和基于树状图的功能多样性（FD），分别作为鸟类生物分类多样性和鸟类提供的生态系统功能的指标，并在类似于苍鹰繁殖栖息地的区域中的30个随机选择的点上执行了相同的步骤。之后，使用广义线性模型，我比较了有和没有苍鹰巢的地方的物种丰富度和FD。因此，我发现苍鹰繁殖场所的存在与鸟类物种丰富度和FD呈显着正相关，解释了这些数据的大部分变异性（物种丰富度：66.4％，FD：66.0％）。综上所述，这些发现表明，苍鹰的繁殖地点可以用作保护替代品，以识别和保护城市生态系统中越冬鸟类的栖息地热点。这些结果可为实施适当的保护措施以维持城市生态系统中鸟类多样性提供基础。