Recording Devices on Free‐Ranging Marine Animals: Does Measurement Affect Foraging Performance?
Recording Devices on Free‐Ranging Marine Animals: Does Measurement Affect Foraging Performance?
复制标题
自由放养海洋动物的记录装置：测量是否会影响觅食性能？
作者：
R. Wilson;W. Grant;D. Duffy
觅食模式的观察对于理解海洋动物的能量生态是必不可少的。然而，在野外直接观察往往不可行，因为大多数觅食发生在海面以下或离陆地很远的地方。将数据记录设备附在动物身上可以极大地促进有意义数据的收集。装置越来越多地用于海洋哺乳动物（Kooyman等人，1976年; Ray等人，1978年）、鸟类（Kooyman等人，1971年，1982年;亚当斯和布朗，1983年;利什曼和克罗克索尔，1983年;威尔逊和贝恩，1984年a，B）、爬行动物（Stoneburner，1982年）和鱼类（Voegeli和Piucock，1980年; Priede，1983年a）。这些设备可以在恢复时提供数据（例如，Kooyman等，1971，1982）或通过遥测到本地接收器（例如，Voegeli和Piucock 1980，Priede 1983 a，B）或轨道卫星（Stoneburner 1982）。仪器质量和挽具附件对陆地动物的影响被认为有可能影响实验和观察的结果（Dumke和Pils，1973年，Gilmeretal。1974年，佩里1981年，佩里塔尔。1981年）。然而，这些装置对生活在比空气粘性大得多的介质中的海洋动物的影响尚未得到评估。在这项研究中，我们调查的影响，附加仪器的觅食活动的非洲企鹅（Spheniscus demersus）。我们表明，仪器的大小可能会对觅食行为产生不利影响，但使用不同大小的设备获得的数据可以用来反算真正的觅食参数自由游泳的企鹅没有设备。数据记录设备在研究自由游泳的企鹅时尤其重要，因为这些鸟类在水面上不显眼，在频繁的旅行和觅食潜水期间也不可见。已经建造了仪器来记录速度（Wilson和Bain 1984 b）、觅食范围（Wilson和Bain 1984 b，Wilson和Awolitner 1985）、潜水时间（Trivelpiece等人，在出版中）、潜水频率和深度（Kooyman等人，1982年; Wilson和Bain，1984年a）。结果表明，非洲企鹅能够保持至少7.5公里/小时的速度（Nagy等人，1984年），其他企鹅物种在超过200米的深度觅食（Kooyman等人，1982年）。觅食距离的测量也被用来估计游泳的能量消耗和构建能量预算（Nagy et al. 1984）。设备可能以两种方式影响性能。一个设备的存在就可能改变行为。然而，根据我们对企鹅的经验，这似乎并不重要;经过一段短时间的调整，非洲企鹅与设备继续其正常的筑巢活动，并进入海洋觅食的频率与控制鸟类相似（威尔逊和贝恩1984年a，B）。其次，装置的质量或阻力可能会减慢游泳速度，从而减少潜水深度，觅食范围和遇到的猎物数量。仪器本身的质量可能不会对觅食行为产生不利影响，因为所连接的设备通常是0.05），这表明最小的仪表对觅食行为几乎没有影响。另一方面，两只企鹅中装有电子测距仪的企鹅占14.6%。
Observations of foraging patterns are essential to understanding the energetic ecology of marine animals. However, direct observations are not often feasible in the field because most foraging takes place below the sea surface or at great distances from land. Attachment of data-recording devices to animals can greatly facilitate the collecton of meaningful data. Devices are being used to an increasing extent on marine mammals (Kooyman et al. 1976, Ray et al. 1978), birds (Kooyman et al. 1971, 1982, Adams and Brown 1983, Lishman and Croxall 1983, Wilson and Bain 1984a, b), reptiles (Stoneburner 1982), and fish (Voegeli and Piucock 1980, Priede 1983a). These devices may supply data upon recovery (e.g., Kooyman et al. 1971, 1982) or through telemetry to local receivers (e.g., Voegeli and Piucock 1980, Priede 1983a, b) or to orbiting satellites (Stoneburner 1982). The effects of instrument mass and harness attachment on land animals are considered to have the potential of affecting the outcomes of experiments and observations (Dumke and Pils 1973, Gilmeretal. 1974, Perry 1981, Perryetal. 1981). However, the effects of devices on marine animals, which live in a much more viscous medium than air, have not been evaluated. In this study we investigated the effects of attached instruments on the foraging activity of the African Penguin (Spheniscus demersus). We show that instrument size may adversely affect foraging behavior, but that data obtained using devices of varying sizes can be used to back-calculate true foraging parameters of free-swimming penguins without devices. Data-recording devices are especially important in studies of free-swimming penguins because these birds are inconspicuous on the surface of the water and are not visible during their frequent traveling and foraging dives. Instruments have been constructed to record speed (Wilson and Bain 1 984b), foraging range (Wilson and Bain 1984b, Wilson and Achleitner 1985), dive time (Trivelpiece et al., in press), dive frequency and depth (Kooyman et al. 1982, Wilson and Bain 1984a). Results show that African Penguins are capable of sustained speeds of at least 7.5 km/h (Nagy et al. 1984) and that other penguin species forage at depths exceeding 200 m (Kooyman et al. 1982). Measurements of foraging distance have also been used to estimate the energy cost of swimming and to construct energy budgets (Nagy et al. 1984). Devices may affect performance in two ways. The mere presence of a device may modify behavior. However, in our experience with penguins this does not appear to be important; after a short period of adjustment, African Penguins with devices continued their normal nesting activity and entered the sea to forage with frequencies similar to control birds (Wilson and Bain 1984a, b). Second, the mass or drag of a device may retard swimming speed, thus reducing dive depth, foraging range, and the number of prey encountered. Instrument mass in itself probably does not adversely influence foraging behavior because attached devices are usually .05) which suggests that the smallest meters had virtually no effect on foraging behavior. On the other hand, two penguins fitted with an electronic distance meter 14.6% of penguin