Movements and foraging of predators associated with mesophotic coral reefs and their potential for linking ecological habitats
Movements and foraging of predators associated with mesophotic coral reefs and their potential for linking ecological habitats
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与中光珊瑚礁相关的捕食者的运动和觅食及其连接生态栖息地的潜力
DOI：
10.3354/meps11110
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发表时间：
2015
影响因子：
2.5
通讯作者：
B. Popp
中科院分区：
文献类型：
--
作者：
Y. Papastamatiou;C. Meyer;R. Kosaki;Natalie J. Wallsgrove;B. Popp
海洋捕食者通常会在特定的栖息地进行昼夜和季节性的运动。在热带地区，中生珊瑚礁可能是许多捕食者的重要栖息地类型，但它们对这些地区的利用很少被调查。我们利用声学遥测和稳定同位素分析的结果，研究了加拉帕戈斯鲨、Carcharhinus Galapagensis和巨型Caranx coinbilis在太平洋一处无人居住的珊瑚礁(深度：50~70m)捕获的昼夜和季节性活动。所有与中层生物礁有关的捕食者都在季节性和周期性的时间范围内进行水平和垂直运动。加拉帕戈斯鲨鱼进行反向潜水垂直运动，夜间潜水比白天深，而巨鲨则表现出混合的状态，一些个体进行有规律的潜水运动(白天深，晚上浅)，另一些个体则进行反向垂直潜水运动。在夏季产卵期间，三叉戟使用很浅的水。捕食者的同位素组成表明，它们主要在浅礁觅食，尽管大约35%的资源来自中生礁。与它们在垂直运动策略上的变异性类似，巨型海鞘占据了广泛的营养位置，可能是由于个体在饮食方面的专业化和种内高度竞争。中生礁可能为上层捕食者提供一些猎物，但也是一个避难栖息地。栖息地之间的频繁移动表明，海洋捕食者可能是营养物质的重要运输者，特别是从浅水礁到中温礁。
Marine predators will often perform diel and seasonal movements associated with specific habitats. In tropical areas, mesophotic coral reefs may be an important habitat type for many predators, but their use of these areas has rarely been investigated. We used results of acoustic telemetry and stable isotope analyses to investigate the diel and seasonal movements of Galapagos sharks Carcharhinus galapagensis and giant trevally Caranx ignobilis captured from a mesophotic reef (depth: 50 to 70 m) at an uninhabited Pacific atoll. All predators associated with mesophotic reefs performed horizontal and vertical movements over seasonal and diel time frames. Galapagos sharks performed reverse diel vertical movements, diving deeper during the night than during the day, while giant trevally displayed a mix, with some individuals performing regular diel movements (deep during the day, shallow at night) and others performing reverse vertical diel movements. Trevally used very shallow water during the summer spawning periods. The isotopic compositions of predators suggest they primarily forage in shallow reefs, although approximately 35% of resources came from mesophotic reefs. Similar to their variability in vertical movement strategies, giant trevally occupied a wide range of trophic positions, potentially due to individual specialization in diet and high levels of intra-specific competition. Mesophotic reefs may provide some prey to upper level predators but also serve as a refuge habitat. The frequent movements between habitats suggest that marine predators may function as significant trans- porters of nutrients, particularly from shallow to mesophotic reefs.