Saavedra Irene, Amo Luisa
Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales (CSIC), C/ José Gutiérrez Abascal, Madrid, Spain.
PLoS One. 2018 Feb 7;13(2):e0190415. doi: 10.1371/journal.pone.0190415. eCollection 2018.
Chemical cues play a fundamental role in mate attraction and mate choice. Lepidopteran females, such as the winter moth (Operophtera brumata), emit pheromones to attract males in the reproductive period. However, these chemical cues could also be eavesdropped by predators. To our knowledge, no studies have examined whether birds can detect pheromones of their prey. O. brumata adults are part of the winter diet of some insectivorous tit species, such as the great tit (Parus major) and blue tit (Cyanistes caeruleus). We performed a field experiment aimed to disentangle whether insectivorous birds can exploit the pheromones emitted by their prey for prey location. We placed artificial larvae and a dispenser on branches of Pyrenean oak trees (Quercus pyrenaica). In half of the trees we placed an O. brumata pheromone dispenser and in the other half we placed a control dispenser. We measured the predation rate of birds on artificial larvae. Our results show that more trees had larvae with signs of avian predation when they contained an O. brumata pheromone than when they contained a control dispenser. Furthermore, the proportion of artificial larvae with signs of avian predation was greater in trees that contained the pheromone than in control trees. Our results indicate that insectivorous birds can exploit the pheromones emitted by moth females to attract males, as a method of prey detection. These results highlight the potential use of insectivorous birds in the biological control of insect pests.
化学信号在配偶吸引和配偶选择中起着至关重要的作用。鳞翅目雌性昆虫，如冬尺蛾（Operophtera brumata），在繁殖期会释放信息素来吸引雄性。然而，这些化学信号也可能被捕食者窃听。据我们所知，尚无研究考察鸟类是否能检测到其猎物的信息素。冬尺蛾成虫是一些食虫山雀物种冬季食物的一部分，如大山雀（Parus major）和蓝山雀（Cyanistes caeruleus）。我们进行了一项野外实验，旨在弄清楚食虫鸟类是否能利用其猎物释放的信息素来定位猎物。我们在比利牛斯橡树（Quercus pyrenaica）的树枝上放置了人工幼虫和一个 dispenser。在一半的树上我们放置了一个冬尺蛾信息素 dispenser，在另一半树上我们放置了一个对照 dispenser。我们测量了鸟类对人工幼虫的捕食率。我们的结果表明，当树上含有冬尺蛾信息素时，有鸟类捕食迹象的幼虫所在的树比含有对照 dispenser 的树更多。此外，含有信息素的树上有鸟类捕食迹象的人工幼虫比例高于对照树。我们的结果表明，食虫鸟类可以利用蛾类雌性释放的信息素来吸引雄性，作为一种猎物检测方法。这些结果凸显了食虫鸟类在害虫生物防治中的潜在用途。
