Jacobson Eiren K, Forney Karin A, Barlow Jay
Scripps Institution of Oceanography, 9500 Gilman Drive, La Jolla, California 92093-0208, USA.
National Oceanographic and Atmospheric Administration, National Marine Fisheries Service, Southwest Fisheries Science Center, 110 Shaffer Road, Santa Cruz, California 95060, USA.
J Acoust Soc Am. 2017 Jan;141(1):219. doi: 10.1121/1.4973415.
Passive acoustic monitoring is a promising approach for monitoring long-term trends in harbor porpoise (Phocoena phocoena) abundance. Before passive acoustic monitoring can be implemented to estimate harbor porpoise abundance, information about the detectability of harbor porpoise is needed to convert recorded numbers of echolocation clicks to harbor porpoise densities. In the present study, paired data from a grid of nine passive acoustic click detectors (C-PODs, Chelonia Ltd., United Kingdom) and three days of simultaneous aerial line-transect visual surveys were collected over a 370 km study area. The focus of the study was estimating the effective detection area of the passive acoustic sensors, which was defined as the product of the sound production rate of individual animals and the area within which those sounds are detected by the passive acoustic sensors. Visually estimated porpoise densities were used as informative priors in a Bayesian model to solve for the effective detection area for individual harbor porpoises. This model-based approach resulted in a posterior distribution of the effective detection area of individual harbor porpoises consistent with previously published values. This technique is a viable alternative for estimating the effective detection area of passive acoustic sensors when other experimental approaches are not feasible.
被动声学监测是一种很有前景的方法，可用于监测港湾鼠海豚（Phocoena phocoena）数量的长期趋势。在实施被动声学监测以估计港湾鼠海豚数量之前，需要有关港湾鼠海豚可探测性的信息，以便将记录的回声定位咔哒声数量转换为港湾鼠海豚密度。在本研究中，在一个370公里的研究区域内，收集了来自由九个被动声学咔哒声探测器（C-PODs，英国Chelonia有限公司）组成的网格的配对数据，以及为期三天的同步空中线状样带视觉调查数据。该研究的重点是估计被动声学传感器的有效探测区域，其定义为个体动物的发声率与被动声学传感器能够检测到这些声音的区域的乘积。在贝叶斯模型中，将视觉估计的鼠海豚密度用作信息先验，以求解个体港湾鼠海豚的有效探测区域。这种基于模型的方法得出的个体港湾鼠海豚有效探测区域的后验分布与先前发表的值一致。当其他实验方法不可行时，该技术是估计被动声学传感器有效探测区域的一种可行替代方法。
