Institute of Experimental Ecology, University of Ulm Ulm, Germany.
Front Physiol. 2013 Nov 25;4:342. doi: 10.3389/fphys.2013.00342. eCollection 2013.
We assessed the behavioral flexibility of the trawling long-legged bat, Macrophyllum macrophyllum (Phyllostomidae) in flight cage experiments by exposing it to prey suspended from nylon threads in the air and to food placed onto the water surface at varying distances to clutter-producing background (water plants). The bat revealed flexibility in foraging mode and caught prey in the air (aerial hawking) and from the water surface (trawling). M. macrophyllum was constrained in finding food very near to and within clutter. As echolocation was the prime sensory mode used by M. macrophyllum for detection and localization of food, the bat might have been unable to perceive sufficient information from prey near clutter as background echoes from the water plant increasingly overlapped with echoes from food. The importance of echolocation for foraging is reflected in a stereotypic call pattern of M. macrophyllum that resembles other aerial insectivorous and trawling bats with a pronounced terminal phase (buzz) prior to capture attempts. Our findings contrast studies of other phyllostomid bats that glean prey very near or from vegetation, often using additional sensory cues, such as prey-produced noise, to find food and that lack a terminal phase in echolocation behavior. In M. macrophyllum, acoustic characteristics of its foraging habitat have shaped its sonar system more than phylogeny.
我们通过在飞行笼实验中让长脚长尾蝠（Macrophyllum macrophyllum，叶口蝠科）接触悬挂在空中的尼龙线上的猎物和放置在水面上不同距离的食物（有杂物产生的背景，如水生植物），评估了其在飞行中的行为灵活性。蝙蝠在觅食模式上表现出灵活性，可以在空中（空中捕食）和从水面（拖网）捕捉猎物。M. macrophyllum 在寻找食物时受到限制，只能在非常靠近杂物和杂物内的地方找到食物。由于回声定位是 M. macrophyllum 用于检测和定位食物的主要感官模式，蝙蝠可能无法从靠近杂物的猎物中获得足够的信息，因为来自水生植物的背景回波与食物回波越来越重叠。回声定位对觅食的重要性反映在 M. macrophyllum 的一种刻板的叫声模式中，这种叫声模式与其他在空中捕食昆虫和拖网的蝙蝠相似，在捕捉猎物之前有一个明显的终末阶段（嗡嗡声）。我们的发现与其他叶口蝠的研究结果形成对比，后者在非常靠近或从植被中采集猎物，通常使用额外的感官线索，如猎物产生的噪音，来寻找食物，并且在回声定位行为中没有终末阶段。在 M. macrophyllum 中，其觅食栖息地的声学特征对其声纳系统的影响大于其系统发育。
