Locomotion in diving elephant seals: physical and physiological constraints
Locomotion in diving elephant seals: physical and physiological constraints
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DOI：
10.1098/rstb.2007.2107
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发表时间：
2007-11-29
影响因子：
6.3
通讯作者：
Weihs, Daniel
中科院分区：
文献类型：
--
作者：
Davis, Randall W.;Weihs, Daniel
为了更好地理解海象（miounga angustirostris）是如何利用负浮力来减少能量代谢和延长潜水时间的，我们模拟了海象在运输和深海觅食潜水时的能量消耗。采用数值积分技术模拟了游泳速度、下降和上升角度以及运动方式（即划水和滑翔）对有氧穿越和觅食潜水的潜水代谢率、有氧潜水极限、垂直位移（最大潜水深度）和水平位移（潜水起点和终点之间沿直线的最大水平距离）的影响。各参数的真实值均取自以往的实验数据。我们的研究结果表明，与水面下水平游泳相比，滑翔下降的过境潜水几乎没有能量优势。其他因素，如觅食和躲避捕食者，可能有利于在迁徙期间潜入深海。滑翔下降为觅食潜水节省了不同的能量。深中水觅食潜水显示出最大的能量节约(大约。18%)，因为在下降过程中滑翔。相比之下，在400米深处水平游泳的平底觅食潜水与滑翔下降相比，表现出较少的能量优势，主要是因为更多的潜水涉及抚摸。在充分了解不同年龄和身体组成的雄性和雌性海象滑翔下降的优势之前，还需要更多的数据。这种类型的数据需要动物携带的仪器，这些仪器可以记录自由放养的动物在深海中的行为、三维运动和运动表现。
To better understand how elephant seals (Mirounga angustirostris) use negative buoyancy to reduce energy metabolism and prolong dive duration, we modelled the energetic cost of transit and deep foraging dives in an elephant seal. A numerical integration technique was used to model the effects of swim speed, descent and ascent angles, and modes of locomotion (i.e. stroking and gliding) on diving metabolic rate, aerobic dive limit, vertical displacement ( maximum dive depth) and horizontal displacement ( maximum horizontal distance along a straight line between the beginning and end locations of the dive) for aerobic transit and foraging dives. Realistic values of the various parameters were taken from previous experimental data. Our results indicate that there is little energetic advantage to transit dives with gliding descent compared with horizontal swimming beneath the surface. Other factors such as feeding and predator avoidance may favour diving to depth during migration. Gliding descent showed variable energy savings for foraging dives. Deep mid-water foraging dives showed the greatest energy savings (approx. 18%) as a result of gliding during descent. In contrast, flat-bottom foraging dives with horizontal swimming at a depth of 400 m showed less of an energetic advantage with gliding descent, primarily because more of the dive involved stroking. Additional data are needed before the advantages of gliding descent can be fully understood for male and female elephant seals of different age and body composition. This type of data will require animal-borne instruments that can record the behaviour, three-dimensional movements and locomotory performance of free-ranging animals at depth.