| 摘要: |
| 利用自制的鱼类游泳能力测定装置, 观察了大海马垂直和水平方向的最大临界游速, 描述了大海马的游泳行为, 并评估其游泳能力。结果表明: 水温25.5℃±1.0℃条件下, 体长6cm个体水平方向的临界游速达到峰值为4.23cm/s±0.23cm/s; 随体长的增加和减少, 临界游速都有所下降, 体长至约10cm时临界游速为2.86cm/s±0.02cm/s。该物种在水平游泳时, 游泳速度与尾部的倾斜角度有关, 倾角越大,速度越大, 当倾角达到55°时, 速度达到最大值, 而大于该角度, 身体就失去平衡不能进行逆水流游动。大海马体长在6cm时达到垂直方向的临界游速峰值, 为0.372cm/s±0.014cm/s, 此时的绝对临界速度为0.085BL/s±0.010BL/s。至体长增长到13cm时, 基本趋于稳定, 与水平方向游速变化趋势相似。 |
| 关键词: 大海马 水平方向 竖直方向 临界速度 游泳能力 |
| DOI：10.11759/hykx20150714001 |
| 分类号: |
| 基金项目:国家自然科学基金(41276123) |
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| Determination and analysis of swimming behavior and swimming ability of yellow seahorse, Hippocampus kuda Bleeker |
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LI Xiang,XU Yong-jian
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| Abstract: |
| In this study, we used a self-made fish swimming capability analysis device to determine and analyze the critical swimming velocity in the horizontal and vertical directions of the yellow seahorse, Hippocampus kuda. Moreover, we describe its swimming behavior and evaluate its swimming ability. The results showed that under different flow velocities, the seahorse adopts different swimming poses. In low flow velocity, the animal moved around with ease with its tail curled. As the flow velocity increased, the tail opened and extended, slowly inclined, and its tilt angle became bigger and bigger in the vertical plane. The critical horizontal swimming velocity was observed to be closely related to the tilt angle. For the yellow seahorse, when the tail angle was between 55° and 60°, its horizontal swimming velocity was at maximum; when the angle was more than 60°, the animal lost its body balance. We observed that the motion power of the seahorse originates from the fins, especially, the pectoral fins, which determine the speed and direction of swimming via different stroke frequencies and water-shifting directions. We observed that when the stroke frequency was between 0.5 and 11 times·s-1, it was in proportion to its swimming velocity. We also observed the relationship between body length and the swimming critical velocity at a temperature of 25.5℃ ± 1.0℃. Moreover, we found that in the horizontal direction, the yellow seahorse had the greatest velocity of 4.23 cm/s ±0.23 cm/s, with its body length varying from 4 to 6 cm, after which the velocity decreased to 2.86 ± 0.02 cm/s for more than 12 cm body length. In the vertical direction, similar to the horizontal direction, the greatest velocity was 0.372 cm/s ± 0.014 cm/s with its body length of approximately 6 cm, and the maximum absolute critical velocity was 0.085 BL/s ±0.010 BL/s. When the body length was more than 13 cm, the velocity was stable. Judging from its swimming behavior and critical velocity, the swimming ability of the yellow seahorse is not strong. |
| Key words: Hippocampus kuda Bleeker, Horizontal direction, Vertical direction, Critical velocity of swimming, Body Length |
