Data from: Impact of spatial variation of a crucial prey, the molecricket, on hoopoe territory occupancy and reproduction

Direct benefits accrued from securing a territory of sufficient quality are important determinants of individual fitness and population persistence. Food supply is one of the main factors of animal territory quality, with spatial and temporal variation in prey availability largely dictating reproductive output and thus population dynamics. In a Swiss hoopoe population, molecrickets Gryllotalpa gryllotalpa, the most profitable prey locally, can constitute most of the food biomass delivered to chicks by parents. We first investigated the impact of molecricket prey on hoopoes’ fitness-related traits by quantifying the spatial variation in the food allocation pattern of both male and female parents to chicks across the whole population range; and second, analysed the impact of this prey on current reproduction and, using a 11 year dataset, on the temporal occupancy rate of each territory. We found considerable but spatially repeatable variation, over the years, of molecricket biomass in the diet provisioned to chicks. This spatial heterogeneity in chicks’ diet composition was mirrored both in the history of territory occupancy (2002-2012) and in current reproductive success (2012). Territories with a greater biomass of molecrickets in chicks’ diet produced more fledglings in better body condition. Yet, these effects on current reproduction were exclusively demonstrated for male parents, corroborating that paternal provisioning patterns play a predominant role in hoopoe reproductive success. This study demonstrates how a single, very profitable prey species might affect spatial variation in territory settlement and individual reproductive success in a regionally endangered bird species, with potential consequences for its population dynamics and persistence.获取优质领地所带来的直接收益，是决定个体适合度与种群存续的关键因素。食物供给是影响动物领地质量的核心要素之一，猎物可获得性的时空变异在很大程度上决定繁殖产出，进而影响种群动态。在瑞士戴胜（hoopoe）种群中，本地最具收益价值的猎物——蝼蛄（molecricket，学名Gryllotalpa gryllotalpa）——可占亲代投喂雏鸟食物生物量的绝大部分。本研究首先通过量化整个种群分布范围内雌雄亲代向雏鸟投喂食物的空间分配模式变异，探究了蝼蛄猎物对戴胜适合度相关性状的影响；其次，利用11年数据集分析了该猎物对当前繁殖的影响，以及对各领地时间维度占用率的作用。研究发现，多年来雏鸟日粮中的蝼蛄生物量存在显著但具有空间重复性的变异。雏鸟日粮组成的这种空间异质性，既体现在2002-2012年的领地占用历史中，也反映在2012年的当前繁殖成功率上。雏鸟日粮中蝼蛄生物量更高的领地，能够抚育出更多体质优良的出飞幼鸟。然而，上述对当前繁殖的影响仅在雄性亲代中得到证实，这印证了雄性亲代的投喂模式在戴胜繁殖成功中发挥主导作用。本研究阐明了单一高收益猎物物种，如何影响区域濒危鸟类的领地定居空间变异与个体繁殖成功率，并对其种群动态与存续产生潜在影响。