Avian occupancy probabilities, vegetation structure, and presence of Northern Bobwhite (Colinus virginianus) in eastern and central Oklahoma (2009-2011)

Changes in land use and land cover throughout the eastern half of North America have caused substantial declines in populations of birds that rely on grassland and shrubland vegetation types, including socially and economically important game birds such as the Northern Bobwhite (Colinus virginianus; hereafter bobwhites). As much attention is focused on habitat management and restoration for bobwhites, they may act as an umbrella species for other bird species with similar habitat requirements. We quantified the relationship of bobwhites to the overall bird community and evaluated the potential for bobwhites to act as an umbrella species for grassland and shrubland birds. We monitored bobwhite presence and bird community composition within 31 sample units on selected private lands in the south-central United States from 2009 to 2011. Bobwhites were strongly associated with other grassland and shrubland birds and were a significant positive predictor for 9 species. Seven of these, including Bell's Vireo (Vireo bellii), Dicksissel (Spiza americana), and Grasshopper Sparrow (Ammodramus savannarum), are listed as species of conservation concern. Species richness and occupancy probability of grassland and shrubland birds were higher relative to the overall bird community in sample units occupied by bobwhites. Our results show that bobwhites can act as an umbrella species for grassland and shrubland birds, although the specific species in any given situation will depend on region and management objectives. These results suggest that efficiency in conservation funding can be increased by using public interest in popular game species to leverage resources to meet multiple conservation objectives.

北美东半部的土地利用与土地覆被变化，导致依赖草原和灌丛植被类型的鸟类种群大幅衰减，其中涵盖兼具社会与经济价值的猎用鸟类，如北美鹑（Northern Bobwhite，Colinus virginianus，下文简称鹑类）。鉴于针对鹑类的栖息地管理与修复研究已备受关注，其或可作为栖息地需求相似的其他鸟类的伞护种。本研究量化了鹑类与整体鸟类群落的关联关系，并评估了其作为草原和灌丛鸟类伞护种的潜力。2009至2011年间，研究团队在美国中南部选定的私有土地上的31个样地内，监测了鹑类的存在情况与鸟类群落组成。结果显示，鹑类与其他草原和灌丛鸟类存在显著关联，且是9个物种的显著正向预测因子。其中7个物种，包括贝尔氏莺（Bell's Vireo，Vireo bellii）、美洲草鹀（Dickcissel，Spiza americana）和草地鹀（Grasshopper Sparrow，Ammodramus savannarum），均被列为保护关注物种。在鹑类栖息的样地中，草原和灌丛鸟类的物种丰富度与栖息概率均高于整体鸟类群落的平均水平。本研究结果表明，尽管特定情境下的伞护物种类会因区域和管理目标有所差异，但鹑类确实可作为草原和灌丛鸟类的伞护种。此外，研究结果还提示，借助大众对热门猎用鸟类的关注度以撬动保护资源，可提升保护资金的使用效能，从而实现多重保护目标。