Many predators reported to feed on crown-of-thorns starfish (CoTS, Acanthaster spp.) are generalist and opportunistic feeders. However, research into predation on CoTS tends to examine these predator–prey interactions in isolation, and it remains unknown whether many potential predators will prey on CoTS when other, potentially more palatable, food sources are available. Assessing predatory responses to changes in prey availability is critical for gauging the capacity of predators to regulate prey populations. Here, we explored prey preferences and tested for prey switching across nine species of planktivorous damselfish offered varying densities of Pacific CoTS ( Acanthaster cf. solaris ) larvae versus larvae of a common and co-occurring starfish, Linckia laevigata . Results show that planktivorous damselfishes will consume crown-of-thorns starfish larvae, even in the presence of alternative prey. Feeding responses varied among the nine planktivorous predators with five damselfishes ( Acanthochromis polyacanthus , Amblyglyphidodon curacao , Dascyllus reticulatus , Pomacentrus amboinensis and Pomacentrus moluccensis ) exhibiting increased consumption of Acanthaster larvae with increasing density, despite the presence of alternative prey. Moreover, Abudefduf sexfasciatus and P. amboinensis exhibited preference for larvae of A. cf. solaris over larvae of L. laevigata . Despite these predation patterns, prey switching between starfish larvae was not observed. These results add to a growing body of evidence which suggests that predators of the early life stages of A. cf. solaris could be important in regulating settlement and recruitment patterns of this starfish, especially at low, non-outbreak, densities.

中文翻译：

---

即使有其他猎物存在，棘冠海星幼虫也容易受到捕食

据报道，许多以棘冠海星（CoTS，Acanthaster spp.）为食的捕食者是多面手和机会主义者。然而，对 CoTS 捕食的研究倾向于孤立地检查这些捕食者 - 猎物的相互作用，并且当其他可能更可口的食物来源可用时，许多潜在的捕食者是否会捕食 CoTS 仍然未知。评估捕食者对猎物可用性变化的反应对于衡量捕食者调节猎物种群的能力至关重要。在这里，我们探索了猎物偏好并测试了 9 种浮游雀鲷的猎物转换，这些雀鲷提供不同密度的太平洋 CoTS（Acanthaster cf. solaris）幼虫与常见和共生海星 Linckia laevigata 的幼虫。结果表明，即使有其他猎物存在，浮游雀鲷也会吃掉棘冠海星幼虫。9 种浮游捕食者与 5 种雀鲷（Acanthochromis polyacanthus、Amblyglyphidodon curacao、Dascyllus reticulatus、Pomacentrus amboinensis 和 Pomacentrus moluccensis）的摄食反应各不相同，尽管存在替代性猎物，但它们对 Acanthaster 幼虫的消耗量增加。此外，Abudefduf sexfasciatus 和 P. amboinensis 表现出对 A. cf. 幼虫的偏好。在 L. laevigata 幼虫上的 solaris 。尽管有这些捕食模式，但没有观察到海星幼虫之间的猎物转换。这些结果增加了越来越多的证据，表明 A. cf. 早期生命阶段的捕食者。