Dynamic body acceleration improves mapping of at‐sea foraging behavior in black‐tailed gulls <i>Larus crassirostris</i>
Dynamic body acceleration improves mapping of at‐sea foraging behavior in black‐tailed gulls <i>Larus crassirostris</i>
复制标题
动态身体加速度改善了黑尾鸥<i>Larus crassirostris</i>海上觅食行为的绘制
DOI：
10.1111/jav.02869
复制
发表时间：
2022
影响因子：
1.7
通讯作者：
Watanuki Yutaka
中科院分区：
文献类型：
--
作者：
Ma Rui;Kazama Kentaro;Yasutake Yogi C.;Kazama Mami T.;Tsukamoto Shota;Watanuki Yutaka
海鸟密集觅食的区域可以通过跟踪个体的海上运动来区分。然而，这样的跟踪数据可能不能准确地反映鸟类确切的觅食地点。除了跟踪数据外，收集个体鸟的动态身体加速度信息可以改进对其觅食活动的推断。我们的目的是利用海鸟身体加速度的数据对其觅食行为进行分类，并利用这一信号来区分它们集中觅食的区域。因此，我们使用GPS记录仪和加速度计分别记录了2017年和2018年7只和10只黑尾鸥的觅食运动和身体加速度数据。通过参考飞行和觅食个体的视频片段，我们可以根据鸟类的速度、身体角度、身体加速度的周期和幅度，对飞行（扑翼飞行、滑翔和悬停）、觅食（表面俯冲、跳跃和游泳）和维持（漂移、整理毛发等）行为进行分类。从加速度数据中确定的觅食区域与从GPS轨迹中确定的低速和区域限制搜索（ARS）区域大致对应。然而，这项研究表明，觅食行为的发生可能被高估了，因为鸟类可能会表现出长时间的减少运动，专门用于维护。相反，基于ARS的方法可能低估了觅食行为，因为鸟类可以在不进行ARS的情况下觅食。因此，我们的研究结果表明，结合使用加速度计和GPS跟踪有助于充分确定黑尾鸥的重要觅食区域。我们的方法可能有助于更好地区分海洋环境中具有生态或生物学意义的区域。
Areas at which seabirds forage intensively can be discriminated by tracking the individuals' at‐sea movements. However, such tracking data may not accurately reflect the birds' exact foraging locations. In addition to tracking data, gathering information on the dynamic body acceleration of individual birds may refine inferences on their foraging activity. Our aim was to classify the foraging behaviors of surface‐feeding seabirds using data on their body acceleration and use this signal to discriminate areas where they forage intensively. Accordingly, we recorded the foraging movements and body acceleration data from seven and ten black‐tailed gullsLarus crassirostrisin 2017 and 2018, respectively, using GPS loggers and accelerometers. By referring to video footage of flying and foraging individuals, we were able to classify flying (flapping flight, gliding and hovering), foraging (surface plunging, hop plunging and swimming) and maintenance (drifting, preening, etc.) behaviors using the speed, body angle and cycle and amplitude of body acceleration of the birds. Foraging areas determined from acceleration data corresponded roughly with sections of low speed and area‐restricted searching (ARS) identified from the GPS tracks. However, this study suggests that the occurrence of foraging behaviors may be overestimated based on low‐speed trip sections, because birds may exhibit long periods of reduced movement devoted to maintenance. Opposite, the ARS‐based approach may underestimate foraging behaviors since birds can forage without conducting an ARS. Therefore, our results show that the combined use of accelerometers and GPS tracking helps to adequately determine the important foraging areas of black‐tailed gulls. Our approach may contribute to better discriminate ecologically or biologically significant areas in marine environments.