Semi-intensive Shrimp-Farms as Experimental Arenas for the Study of Predation Risk from Falcons to Shorebirds

Varying environmental conditions and energetic demands can affect habitat use by predators and their prey. Anthropogenic habitats may provide an opportunity to document both predation events and foraging activity by prey, and therefore enable an empirical evaluation how prey cope with trade-offs between starvation and predation risk in environments of variable foraging opportunities and predation danger. Here we use seven years of observational data of peregrine falcons Falco peregrinus and shorebirds at a semi-intensive shrimp-farm to determine how starvation and predation risk vary for shorebirds under a predictable variation in foraging opportunities. Attack rate (mean 0.1 attacks/hr, equating 1 attack every ten hours) was positively associated with the total foraging area available for shorebirds at the shrimp-farm throughout the harvesting period, with tidal amplitude at the adjacent mudflat having a strong non-linear (quadratic) effect. Hunt success (mean 14%) was higher during lo...多变的环境条件与能量需求，可影响捕食者及其猎物的栖息地利用模式。人为营造的栖息地可为记录捕食事件与猎物的觅食行为提供契机，进而可开展实证评估，解析猎物在觅食机会与捕食风险均存在波动的环境中，如何平衡饥饿风险与被捕食压力间的取舍关系。本研究依托一处半集约化养虾场（semi-intensive shrimp-farm）内为期七年的游隼（Falco peregrinus）与滨鸟（shorebirds）观测数据，旨在探究在觅食机会可预测波动的情境下，滨鸟面临的饥饿风险与被捕食风险如何变化。攻击率（均值为0.1次/小时，即每10小时发生1次攻击）与收获期内养虾场可供滨鸟使用的总觅食面积呈正相关；相邻潮间带泥滩的潮汐振幅则对其产生显著的非线性（二次）效应。捕猎成功率（均值为14%）在……期间更高