Fiore Cara, Tull Jamie L, Zehner Sean, Ducey Peter K
Department of Biological Sciences, State University of New York College at Cortland, Cortland, NY 13045, USA.
Behav Processes. 2004 Nov 30;67(3):327-34. doi: 10.1016/j.beproc.2004.06.001.
The potential ecological impact of exotic terrestrial planarians will be determined in part by their sensory abilities and predatory behavior. It has been suggested that these flatworms may only encounter their earthworm prey by chance, hence restricting the breadth of species they will feed upon and the number of microhabitats in which predator-prey interactions occur. We hypothesized that those flatworms that have already successfully invaded North America (genus Bipalium) actually detect and follow chemical trails of earthworms and possess the behavioral repertoire needed to feed on the prey in a range of microhabitats. We examined: (1) the tendency of Bipalium adventitium to follow chemical trails left by injured and un-injured earthworms; (2) the behavioral repertoire and predatory success of B. adventitium feeding on three earthworm species in subterranean tunnels; and (3) the response of flatworms to the reportedly defensive secretions of the earthworm Eisenia fetida in tunnels. B. adventitium detected and followed trails of earthworm mucus and secretions left by injured and un-injured earthworms. Flatworms followed trails on a range of substrates and pursued and captured three species of earthworms in subterranean tunnels, including individuals many times their mass. Although most behavior exhibited during underground attacks was similar to that reported for surface encounters, the flatworms also behaved in ways that blocked earthworm escape from tunnels. The flatworms were less successful at preying on E. fetida than on Lumbricus rubellus and Lumbricus terrestris in underground tunnels and showed some aversion to the secretions from E. fetida.
外来陆生涡虫的潜在生态影响将部分取决于它们的感官能力和捕食行为。有人认为，这些扁虫可能只是偶然遇到蚯蚓猎物，因此限制了它们捕食的物种范围以及捕食者与猎物相互作用发生的微生境数量。我们假设那些已经成功入侵北美的扁虫（双盘属）实际上能够检测并追踪蚯蚓的化学踪迹，并且具备在一系列微生境中捕食猎物所需的行为能力。我们研究了：（1）外来双盘扁虫追踪受伤和未受伤蚯蚓留下的化学踪迹的倾向；（2）外来双盘扁虫在地下隧道中捕食三种蚯蚓物种时的行为能力和捕食成功率；（3）扁虫对蚯蚓赤子爱胜蚓在隧道中据报道的防御性分泌物的反应。外来双盘扁虫能够检测并追踪受伤和未受伤蚯蚓留下的黏液和分泌物踪迹。扁虫在一系列基质上追踪踪迹，并在地下隧道中追捕并捕获了三种蚯蚓，包括比它们体型大很多倍的个体。尽管地下攻击时表现出的大多数行为与在地表相遇时报道的行为相似，但扁虫也会采取一些方式阻止蚯蚓从隧道逃脱。在地下隧道中，扁虫捕食赤子爱胜蚓的成功率低于捕食红蚯蚓和正蚓，并且对赤子爱胜蚓的分泌物表现出一定的厌恶。
