Passive acoustic density estimation of sperm whales in the Tongue of the Ocean, Bahamas
Passive acoustic density estimation of sperm whales in the Tongue of the Ocean, Bahamas
复制标题
巴哈马海舌抹香鲸的被动声密度估计
DOI：
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
P. Tyack
中科院分区：
文献类型：
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作者：
J. A. W. Ard;L. Thomas;S. Jarvis;N. Dimarzio;D. Moretti;T. Marques;Charlotte A. Dunn;Diane C laridge;E. Hartvig;P. Tyack
对海军范围内海洋哺乳动物的长期被动声学监测为更好地了解声纳对种群的潜在影响提供了机会。巴哈马群岛海洋之舌（TOTO）的海军范围包含广泛的水听器阵列，潜在地允许估计深潜，声音活跃的物种的密度，如抹香鲸（Physeter macrocephalus）。以前在TOTO进行的目视调查的时空覆盖范围有限，结果只是零星地看到抹香鲸，而被动的声学观察表明，该物种全年都有。然而，到目前为止，声学方法确定每个集群中个体的具体数量是有限的。我们使用最近开发的算法来确定在42天的研究期间出现的回声定位鲸的数量。我们筛选了297小时的声学数据集，以确定动物存在的时间比例；分析了在场期间的50个10分钟样本，以估计每个样本中发声的个体数量。这些计数与对标记动物发声10分钟的独立估计相结合。估计平均密度为0.16头鲸鱼/ 1000 km2 （CV 27%; 95% CI 0.095-0.264）。该方法可能适用于其他包含密集水听器阵列的区域。
Long-term passive acoustic monitoring of marine mammals on navy ranges provides the opportunity to better understand the potential impact of sonar on populations. The navy range in Tongue of the Ocean (TOTO), Bahamas contains extensive hydrophone arrays, potentially allowing estimation of the density of deep diving, vocally active species such as the sperm whale (Physeter macrocephalus). Previous visual surveys in TOTO have been of limited spatio–temporal coverage and resulted in only sporadic sightings of sperm whales, whereas passive acoustic observations suggest the species is present year round. However, until now the means of acoustically determining the specific number of individuals in each cluster has been limited. We used recently developed algorithms to identify the number of echolocating whales present during a 42 d study period. We screened a 297 h acoustic data set to determine the proportion of time animals were present; fifty 10 min samples during presence were analyzed to estimate the number of individuals vocalizing during each sample. These counts were combined with an independent estimate of the proportion of 10 min periods when tagged animals vocalize. The estimated average density was 0.16 whales/1,000 km 2 (CV 27%; 95% CI 0.095–0.264). The method is potentially applicable to other areas containing dense hydrophone arrays.