Dive behaviour impacts the ability of heart rate to predict oxygen consumption in Steller sea lions (Eumetopias jubatus) foraging at depth
Dive behaviour impacts the ability of heart rate to predict oxygen consumption in Steller sea lions (Eumetopias jubatus) foraging at depth
复制标题
潜水行为影响心率预测北海狮 (Eumetopias jubatus) 在深海觅食的耗氧量的能力
DOI：
10.1242/jeb.047340
复制
发表时间：
2011
影响因子：
2.8
通讯作者：
A. Trites
中科院分区：
文献类型：
--
作者：
B. Young;D. Rosen;A. Hindle;M. Haulena;A. Trites
对几种水平游泳或浅水潜水的海洋哺乳动物，我们推导出了心率（fH）和耗氧量（）之间的预测关系。然而，目前尚不清楚潜水活动如何影响这种关系，也不清楚现有的方程是否适用于潜入更深深度的动物。我们通过同时测量虎头海狮（Eumetopias jubatus）在不同活动状态（水面休息或潜水）、潜水类型（单次潜水或潜水回合）和深度（10或40米）下的fH和来调查这些问题。我们只研究了潜水和潜水周期（潜水+水面间隔）之间的关系。我们发现fH只能预测一个完整的单次潜水周期或一次潜水周期（即必须包括表面间隔）。海狮在水面上休息的预测方程与单次潜水周期的预测方程没有区别。然而，在潜水周期（多次潜水+水面间隔）下推导的方程与单次潜水周期或水面休息时推导的方程不同，多次潜水周期方程的相似fH比单次潜水周期（或休息）的预测更高。在测试条件下，潜水时间、潜水深度、水温和累积食物消耗对这种关系没有显著影响。最后，我们的研究结果表明，fH可以用来预测潜水的刺头海狮的活动特异性代谢率，但仅适用于包括潜水后水面恢复期在内的完整潜水周期。
SUMMARY The predictive relationship between heart rate (fH) and oxygen consumption () has been derived for several species of marine mammals swimming horizontally or diving in tanks to shallow depths. However, it is unclear how dive activity affects the relationship and whether the existing equations apply to animals diving to deeper depths. We investigated these questions by simultaneously measuring the fH and of Steller sea lions (Eumetopias jubatus) under different activity states (surface resting or diving), types of dives (single dives or dive bouts), and depths (10 or 40 m). We examined the relationship over dives only and also over dive cycles (dive + surface interval). We found that fH could only predict over a complete single dive cycle or dive bout cycle (i.e. surface intervals had to be included). The predictive equation derived for sea lions resting on the surface did not differ from that for single dive cycles. However, the equation derived over dive bout cycles (multiple dives + surface intervals) differed from those for single dive cycles or surface resting, with similar fH for multiple dive bout equations yielding higher predicted than that for single dive bout cycles (or resting). The relationships were not significantly affected by dive duration, dive depth, water temperature or cumulative food consumed under the conditions tested. Ultimately, our results demonstrate that fH can be used to predict activity-specific metabolic rates of diving Steller sea lions, but only over complete dive cycles that include a post-dive surface recovery period.