当前位置: X-MOL 学术Fish. Res. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Differences in the behavioral characteristics between green and loggerhead turtles in a setnet bycatch simulation
Fisheries Research ( IF 2.2 ) Pub Date : 2021-06-11 , DOI: 10.1016/j.fishres.2021.106036
Daisuke Shiode , Jun Okamoto , Maika Shiozawa , Keiichi Uchida , Yoshinori Miyamoto , Fuxiang Hu , Tadashi Tokai

Sea turtles that have entered the submerged bag net of setnets repeatedly push their heads up against the ceiling netting (referred to here as push-ups) to ascend to breathe. Consecutive push-ups are essential to the success of escaping in a turtle releasing system developed to reduce the incidental death in setnets. Existence of differences in behavioral characteristics were suggested among turtle species, but no detailed evaluation has been performed. The objectives of this study were to establish extraction methods of the consecutive push-ups with a tri-axial acceleration logger, and to clarify the differences in the behavioral characteristics between green Chleonia mydas and loggerhead Caretta caretta turtles under the simulated condition of bycatch in setnets for appropriate adaptation and modification of this system. The behavior of each turtle mounted with an acceleration logger in an experimental bag net was recorded using a video camera. The consecutive push-ups were extracted by filtering the time-series body angle converted from the static surge acceleration and the overall dynamic body acceleration (ODBA) from the triaxial dynamic acceleration. A threshold of 20° in body angle and 1.0 m/s2 in ODBA was detected among 89 % of all consecutive push-ups in green turtles. On the other hand, the ODBA was not adopted as the extract condition in loggerhead turtles, although a threshold of 20° in the body angle detected 93 % correctly. Mode of ODBA (1.0–1.5 m/s2) in the green turtles was larger than that in the loggerhead turtles (0.5–1.0 m/s2) during consecutive push-ups. In contrast, the number and duration of the consecutive push-ups in the green turtles were less than those of loggerhead turtles. Consequently, modifying the gear with a larger inclination angle of the ceiling netting should be considered for the setnets where the bycatch of green turtles dominates.



中文翻译:

集网兼捕模拟中绿海龟和红海龟行为特征的差异

进入固定网的水下袋网的海龟反复将头顶在天花板网上(此处称为俯卧撑)以上升呼吸。连续俯卧撑对于成功逃脱海龟释放系统至关重要,该系统旨在减少 setnets 中的意外死亡。海龟物种之间的行为特征存在差异,但尚未进行详细评估。本研究的目的是建立连续俯卧撑与三轴加速度记录器的提取方法,并澄清绿色之间的行为特征的差异Chleonia海龟和龟科圆科圆在 setnets 中模拟条件下的兼捕条件下的海龟,以适当地适应和修改该系统。使用摄像机记录每只乌龟在实验袋网中安装有加速度记录器的行为。连续俯卧撑是通过过滤从静态喘振加速度转换的时间序列身体角度和从三轴动态加速度转换的整体动态身体加速度(ODBA)来提取的。在 89% 的绿海龟连续俯卧撑中检测到20° 的身体角度阈值和 1.0 m/s 2的 ODBA。另一方面,虽然 20° 的身体角度阈值检测到 93% 正确,但并未采用 ODBA 作为红海龟的提取条件。ODBA 模式 (1.0–1.5 m/s 2) 在连续俯卧撑期间,绿海龟比红海龟 (0.5–1.0 m/s 2 ) 大。相比之下,绿海龟连续俯卧撑的次数和持续时间都少于蠵龟。因此,对于绿海龟的兼捕占主导地位的固定网,应考虑修改具有更大倾斜角度的天花板网的齿轮。

更新日期:2021-06-11
down
wechat
bug