The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, People's Republic of China.
J Acoust Soc Am. 2011 Oct;130(4):2285-92. doi: 10.1121/1.3625257.
In order to periodically investigate the population and distribution of the Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) in its main distribution range in the Yangtze River, a passive acoustic system deployed on a cargo ship as a moving platform, rather than a dedicated research ship, was developed. A stereo acoustic event data-logger (A-tag) was installed on the cargo ship to passively detect phonating animals. In three surveys carried out in the Yangtze River from Wuhan to Shanghai, an average of 6059 clicks in each survey and 284 porpoises in total were acoustically detected along an 1100-km stretch. The animals were detected frequently in most of the survey range except two "gap sections" with 40 and 60 km lengths, respectively, where no animals were detected in all three surveys. Detected group sizes of the animals in each 120-s time window were not significantly different among the surveys, but the distribution pattern was different and suggested seasonal migration. The cargo ship based passive acoustic survey was effective in detecting phonating animals and can potentially monitor the distribution and population trend over time. Compared to surveys that used dedicated research ships, the present method is more cost effective.
为了定期调查长江中下游江豚（Neophocaena asiaeorientalis asiaeorientalis）的种群数量和分布情况，本研究开发了一种基于货船的被动声学系统，将其作为移动平台，而不是专用研究船。在货船上安装了立体声学事件数据记录器（A-tag），以被动探测发声动物。在武汉至上海的长江三次调查中，平均每次调查检测到 6059 次咔哒声，共检测到 284 头江豚。除了两个分别长 40 和 60 公里的“空白段”外，在大部分调查范围内都频繁检测到动物，在所有三次调查中均未在这两段检测到动物。在每个 120 秒时间窗口中，动物的检测到的群体大小在三次调查中没有显著差异，但分布模式不同，表明存在季节性洄游。基于货船的被动声学调查在检测发声动物方面非常有效，并且可以潜在地监测随着时间的推移的分布和种群趋势。与使用专用研究船的调查相比，本方法具有更高的成本效益。
