...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Marine ecology progress series >When foraging becomes unprofitable: energetics of diving in tidal currents by common eiders wintering in the Arctic
【24h】

When foraging becomes unprofitable: energetics of diving in tidal currents by common eiders wintering in the Arctic

机译：当觅食变得无利可图时：北极越冬的普通绒毛潜入潮汐的精力充沛

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A variety of ecological, physiological and environmental factors influence the energy budgets of diving animals. For common eiders Somateria mollissima sedentaria wintering in sea ice habitats in the Canadian Arctic, time and energy costs of diving increase exponentially with tidal current speed. Here we use literature estimates of diving energetics and underwater dive data to quantitatively model net energy gain per dive cycle as a function of current speed. The model indicates a strong non-linear decrease in the profitability of diving with increasing currents, predicting that net energy gain per dive cycle will reach zero and become unprofitable at 1.21 m s~(-1) (at 11.3 m depth using baseline parameters from our study). As currents increase travel time, foraging time at the bottom decreases non-linearly, reaching a point where intake is inadequate to balance increasing diving and surface swimming costs. Sensitivity analysis indicates that this threshold is robust over a range of energy expenditure rates and is influenced most by energy intake rate, emphasising the importance of ecological factors such as prey abundance and quality. Eiders stop foraging and rest on the ice well below this threshold in weaker current regimes (～0.8 m s~(-1)), at about the point when profitability begins to decelerate. Behavioural time series of diving under constraints of strong tidal current regimes indicate that these eiders do occasionally dive in currents up to ～1.2 m s~(-1), providing support for the energetic model. Eiders did not dive in faster currents, which could also be influenced by a physiological limit to swimming speed. We conclude that ocean currents can cause a non-linear decrease in net energy balance and are therefore an important and understudied consideration for diving animals. Many functional aspects of diving (e.g. locomotor costs or convective heat loss) have non-linear characteristics; these diminishing returns can be expected to play an important role in the dynamics of behavioural routines and the ability of organisms to respond to environmental variation.
机译：各种生态，生理和环境因素都会影响潜水动物的能量收支。对于加拿大北极海冰栖息地中常见的绒毛猴（Somateria mollissima sedentaria）越冬，潜水的时间和能源成本随着潮流的速度呈指数增长。在这里，我们使用有关潜水高能学和水下潜水数据的文献估计，来定量模拟每个潜水周期的净能量收益作为当前速度的函数。该模型表明，随着电流的增加，潜水的获利能力将出现严重的非线性下降，并预测使用每一个潜水周期的净能量增益将为零，并且在1.21 ms〜（-1）（在11.3 m深度处使用根据我们的基线参数得出的利润）变得无利可图。研究）。随着水流增加行进时间，底部的觅食时间呈非线性下降，达到摄入不足以平衡增加的潜水和水面游泳费用的程度。敏感性分析表明，该阈值在一定范围的能量消耗率上是稳健的，并且受能量摄入率的影响最大，强调了生态因素（例如猎物的丰度和质量）的重要性。在当前较弱的情况下（约0.8 m s〜（-1）），绒毛停止觅食，并在远低于该阈值的冰面上停留，大约在盈利能力开始下降的时候。在强潮流潮流约束下的潜水行为时间序列表明，这些绒毛偶尔会潜入约1.2 m s〜（-1）的水流，这为能量模型提供了支持。绒鸭没有潜入较快的水流中，这也可能受到生理上游泳速度的限制。我们得出的结论是，洋流会导致净能量平衡出现非线性下降，因此是潜水动物的重要且研究不足的考虑因素。潜水的许多功能方面（例如运动成本或对流热损失）具有非线性特征；这些递减的收益可以预期在行为习惯的动态变化和生物对环境变化的响应能力中发挥重要作用。

著录项

相似文献

  • 外文文献
  • 中文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号