Data from: Multidimensional differentiation in foraging resource use during breeding of two sympatric raptors: space, habitat type, time and food

Ecologically-similar species were found to develop specific strategies to partition their resources, leading to niche differentiation and divergence, in order to avoid interspecific competition. Our study determines multi-dimensional differentiation of two sympatric top-predators, long-legged buzzards (LLB) and short-toed eagles (STE), which recently became sympatric during their breeding season in the Judean Foothills, Israel. By combining information from comprehensive diet and movement analyses we found four dimensions of differentiation: (1) Geographic foraging area: LLB tended to forage relatively close to their nests (2.35 ± 0.62 km), while STE forage far from their nest (13.03 ± 2.20 km); (2) Foraging-habitat type: LLBs forage at low natural vegetation, avoiding cultivated fields, whereas STEs forage in cultivated fields, avoiding low natural vegetation; (3) Diurnal dynamics of foraging: LLBs are uniformly active during daytime, whereas STEs activity peaks in the early afternoon; and (4) Food-niche: while both species largely rely on reptiles (47.8% and 76.3% for LLB and STE, respectively), LLB had a more diverse diet and consumed significantly higher percentages of lizards, while STE consumed significantly higher percentages of snakes. Our results suggest that this multidimensional differentiation allows the spatial coexistence of these two dense populations in the study area.

研究表明，生态位相似的物种会演化出专属的资源分配策略，以实现生态位（niche）分化与分异，从而规避种间竞争（interspecific competition）。本研究针对两种同域分布（sympatric）的顶位捕食者（top-predator）——长脚鵟（long-legged buzzards, LLB）与短趾雕（short-toed eagles, STE）的多维分化展开分析；这两个物种近期在以色列朱迪亚山麓（Judean Foothills）的繁殖季形成了同域分布格局。通过整合全面的食性与运动行为分析数据，本研究揭示了四类分化维度：（1）觅食地理范围：长脚鵟的觅食活动多集中于巢穴周边（2.35±0.62千米），而短趾雕的觅食距离则远距巢穴（13.03±2.20千米）；（2）觅食生境类型：长脚鵟偏好低矮自然植被生境，规避农田；短趾雕则反之，以农田为主要觅食生境，避开低矮自然植被区域；（3）日间觅食动态：长脚鵟在日间活动分布较为均匀，而短趾雕的活动高峰出现在午后早些时段；（4）食物生态位（food-niche）：尽管两个物种均主要以爬行动物为食（长脚鵟与短趾雕的爬行动物占比分别为47.8%与76.3%），但长脚鵟的食性更为多样，且蜥蜴占比显著更高；而短趾雕的蛇类占比则显著更高。本研究结果显示，这种多维分化使得这两个高密度种群能够在研究区域内实现空间共存。