Study on marine animal behavior by micro-data tag

为了研究海洋动物的行为，我们开发了微型数据记录器，部署在动物的背部，测量潜水深度，环境温度，盐度，游泳速度，加速度运动，心率和光照水平。我们对港湾鼠海豚、小海雀、鸬鹚、帝企鹅、红海龟和鲑鱼进行了实地实验。这些研究中使用的数据记录仪直径分别为14毫米和19毫米，长度为75毫米。在单个数据记录仪上安装两个或三个传感器，在同一时间尺度内同时测量多个参数。虽然对数据的详细处理和分析仍在进行中，但我们可以从初步分析中得出以下几个独特的发现。港鼠海豚不间断地潜入水中，不会在水面停留更长时间。当他们连续潜水时，他们有两种类型的潜水剖面，浅和深。在潜水过程中，它们的代谢率也很低（18ml O_2/m）。小海雀，体重500g，下潜2-3分钟，下潜深度50米。这次潜水时间远远超过了计算的有氧潜水极限。根据研究结果，我们推测小海雀这种较小的潜水鸟类发展出了生理潜水适应，以减少乳酸增加的影响。鲑鱼垂直运动频繁，范围在0 ~ 150米，有时会向较深的水域游去，以避开温度较高的水域。研究还表明，当它们从海水进入河流时，淡水区不再是障碍。

To investigate behavior of marine animals, we developed the micro-data loggers which is deployed on the back of the animals to measure dive depth, ambient temperature, salinity, swim velocity, acceleration movement, heart rate and light level.We conducted the field experiment on harbor porpoises, auklets, cormorants, king penguins, loggerhead turtles and chum salmons. Those data loggers used in these studies were 14mm and 19mm in diameter and, 75mm in length. Two or three sensors were equipped on a single data logger to measure several parameters simultaneously in the same time scale.Although detailed processing and analysis of data is still under going, we could obtained several unique findings from preliminary analysis as followings.1. Harbor porpoises dived continuously without taking any extended surface time. While their continuous diving, they had two type of dive profiles, shallow and deep. They also maintained low metabolic rate during diving (18ml O_2/m).2. Auklet, 500g body mass, dived for 2-3 minutes and reached 50m depth. This dive duration was far exceeded it's calculated aerobic dive limit. From the results we hypothesized that auklet, smaller diving birds developed physiological dive adaptation to diminish effect of increased lactic acids.3. Chum salmons showed frequent vertical movement ranging 0-150m, and sometimes avoid the warm temperature waters by swimming deeper waters. It also showed that fresh water zone was no longer barrier when they went up to the river from sea water.