PDF(Pubmed)
Abstract：
Many native insects have evolved defenses against native predators. However, their defenses may not protect them from non-native predators due to a limited shared history. The American bullfrog, Aquarana catesbeiana (Anura: Ranidae), which has been intentionally introduced to many countries, is believed to impact native aquatic animals through direct predation. Adults of whirligig beetles (Coleoptera: Gyrinidae), known for swimming and foraging on the water surface of ponds and streams, reportedly possess chemical defenses against aquatic predators, such as fish. Although whirligig beetles potentially encounter both bullfrogs and other frogs in ponds and lakes, the effectiveness of their defenses against frogs has been rarely studied. To assess whether whirligig beetles can defend against native and non-native frogs, we observed the behavioral responses of the native pond frog, Pelophylax nigromaculatus (Anura: Ranidae), and the invasive non-native bullfrog, A. catesbeiana, to native whirligig beetles, Gyrinus japonicus and Dineutus orientalis, in Japan. Adults of whirligig beetles were provided to frogs under laboratory conditions. Forty percent of G. japonicus and D.orientalis were rejected by P. nigromaculatus, while all whirligig beetles were easily consumed by A. catesbeiana. Chemical and other secondary defenses of G. japonicus and D. orientalis were effective for some individuals of P. nigromaculatus but not for any individuals of A. catesbeiana. These results suggest that native whirligig beetles suffer predation by invasive non-native bullfrogs in local ponds and lakes in Japan.
摘要：
许多本地昆虫已经进化了对本地捕食者的防御。然而,由于共享历史有限，他们的防御可能无法保护他们免受非本地掠食者的侵害。美国牛蛙，Aquaranacatesbeiana(Anura:Ranidae)，它被有意引入许多国家，被认为通过直接捕食影响本地水生动物。Whirligig甲虫（鞘翅目：Gyrinidae）的成虫，以在池塘和溪流的水面游泳和觅食而闻名，据报道，对水生捕食者拥有化学防御，比如鱼。尽管Whirligig甲虫可能会在池塘和湖泊中遇到牛蛙和其他青蛙，很少研究它们防御青蛙的有效性。为了评估Whirligig甲虫是否可以防御本地和非本地青蛙，我们观察了本地池塘蛙的行为反应，黑斑Pelophylaxnigromaculatus(Anura:Ranidae)，和侵入性非本地牛蛙，A.Catesbeiana，对本地惠利吉格甲虫来说，日本毛虫和东方神志，在日本。在实验室条件下，将Whirligig甲虫的成虫提供给青蛙。40%的刺槐和东方D.被黑斑P.nigromaculatus排斥，而所有惠利吉格甲虫都很容易被A.catesbeiana食用。日本刺槐和东方山梨的化学和其他次要防御措施对某些黑斑斑蟹的个体有效，但对任何个体均无效。这些结果表明，在日本当地的池塘和湖泊中，本地的Whirligig甲虫遭受了侵入性非本地牛蛙的捕食。
