In environments driven by unpredictable resource pulses, populations of many consumer species experience dramatic fluctuations in abundance and spatial extent. Predator–prey relationships in these acyclic systems are poorly understood in particular with respect to the level of prey specialisation shown by nomadic predators. To understand the dynamics of such a system I examined the response to rodent outbreaks by the letter-winged kite (Elanus scriptus) in the Simpson Desert, Australia; a region that experiences major pulses in primary productivity, driven by unpredictable rainfall events. The kite feeds on small mammals and is the only night-hunting species in the Accipitridae. Letter-winged kites irrupted in the area on only three occasions during 20 years of sampling (1999–2019) and remained for a maximum of 20 months. Each period of kite occupation occurred only during the increase and/or peak phase of rodent population cycles (which occurred three times during the study). During each period kite diet was dominated by small (10–50 g body mass) quadrupedal rodents (Pseudomys australis, P. hermannsburgensis, Mus musculus). Abundance of these species varied across the three outbreaks and kites typically captured them in proportion to availability. The large body mass (134 g) long-haired rat (Rattus villosissimus) was abundant during one outbreak but was infrequently consumed. The bipedal spinifex hopping-mouse (Notomys alexis) was within the kites’ favoured prey size range (35 g) but was consistently avoided. The flexibility in prey selection by letter-winged kites appears to be an important adaptation for survival and reproduction by species exploiting acyclic rodent outbreaks.

在不可预知的资源脉冲驱动的环境中，许多消费物种的种群在数量和空间范围上都经历了剧烈的波动。在这些非循环系统中，尤其是关于游牧性掠食者所表现出的猎物专业化水平，人们对这种掠食者与猎物的关系了解得很少。为了了解这种系统的动态性，我研究了信翅风筝（Elanus scriptus）对啮齿类动物暴发的反应。）在澳大利亚的辛普森沙漠中；在不可预测的降雨事件的驱动下，该地区的初级生产力出现了重大波动。风筝以小型哺乳动物为食，是is科中唯一的夜间狩猎物种。在采样的20年（1999-2019年）中，只有三只信翅风筝在该地区爆发，并且最长持续了20个月。风筝占领的每个时期仅发生在啮齿动物种群周期的增加和/或高峰阶段（在研究期间发生过3次）。在每个时期，风筝的饮食都以小（10–50 g体重）的四足啮齿动物（Pseudomys australis，P.hermannsburgensis，Mus musculus）为主。）。在三个疫情爆发期间，这些物种的丰富度各不相同，而风筝通常会根据可获得性成比例地捕获它们。一次暴发期间，体重较大的长毛鼠（Rattus villosissimus）大（134 g）丰富，但很少食用。双足棘突跳鼠（Notomys alexis）处于风筝偏爱的猎物大小范围（35 g）之内，但始终避免使用。信翅风筝选择猎物的灵活性似乎是利用无环啮齿类动物暴发的物种对生存和繁殖的重要适应。