Factors affecting the response of Seychelles Scops-owl Otus insularis to playback of conspecific calls: consequences for monitoring and management
Factors affecting the response of Seychelles Scops-owl Otus insularis to playback of conspecific calls: consequences for monitoring and management
复制标题
影响塞舌尔角鸮 Otus insularis 对同种叫声播放反应的因素：监测和管理的后果
DOI：
10.1017/s0959270902002228
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发表时间：
2002
影响因子：
1.6
通讯作者：
N. Shah
中科院分区：
文献类型：
--
作者：
D. Currie;J. Millett;M. Hill;N. Shah
塞舌尔特有的岛鸮（Otus insularis）是一种极度濒危的限制范围物种，目前仅在马绍尔的高地森林中有记录，马绍尔是塞舌尔花岗岩岛屿中最大（152平方公里）和最高（903米）的岛屿。我们研究了带色环的个体对同一呼叫回放的反应，以确定影响回放反应的因素，监测行为并评估当前监测技术的可靠性。在1999年4月至2001年5月期间，研究人员每月在固定地点（相距约200米）沿总长度为8.4公里的样带播放地盘鸣叫。根据被标记个体的反应和运动，我们确定了12个领地并标出了它们的边界。平均领土长度为2.92点（约400米），相当于保守估计的领土面积约12-16公顷。雄性比雌性/对更容易被发现。领地上的检出率（雄性对雌性/对）为0.87对0.50；0.65 vs.领土内定点0.26；0.58 vs. 0.22沿样条的固定点。在领地内的定点上，雄鼠和对鼠的检出率均有显著的季节变化，总体上6 - 8月检出率低，4月检出率高，10月检出率低。反应时间和猫头鹰记录器距离不受月相或回放时间的影响。本研究提供了第一个关于塞舌尔鸮对系统重复使用回放的个体反应的基线数据。我们讨论了当前监测的意义及其在其他类似Otus物种中的应用。
The endemic Seychelles Scops-owl Otus insularis is a Critically Endangered restricted range species currently only recorded in the upland forest of Mahé, the largest (152 km2) and highest (903 m) island in the granitic Seychelles. We studied the response of colour-ringed individuals to playback of conspecific calls, to determine factors affecting playback reaction, to monitor behaviour and to assess the reliability of current monitoring techniques. Playback of the territorial waugh call was conducted at fixed points (c. 200 m apart) every month along a total transect length of 8.4 km between April 1999 and May 2001. On the basis of responses and movements of marked individuals we identified 12 territories and noted their boundaries. Mean territory length was 2.92 points (approximately 400 m), equivalent to a conservative estimated territory size of c. 12–16 ha. Males were more frequently detected than females/pairs. The probability of detection (males vs. females/pairs) was 0.87 vs. 0.50 on territory; 0.65 vs. 0.26 at fixed points within territories; and 0.58 vs. 0.22 at fixed points along the transect. There was some significant seasonal variation in detection rates at fixed points within territories for both males and pairs, and in general there was a low probability of detecting individuals around June-August and a high probability of detection around April and, to a lesser degree, October. Response times and owl-recorder distances were not influenced by moon phase or time of playback. This study provides the first baseline data on individual responses to the systematic repeated use of playback in Seychelles Scops-owl. We discuss the implications for current monitoring and its application to other similar Otus species.