Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, 0205 La Jolla, California 92093, USA.
J Acoust Soc Am. 2011 Jul;130(1):557-67. doi: 10.1121/1.3592213.
Surface behavior and concurrent underwater vocalizations were recorded for Pacific white-sided dolphins in the Southern California Bight (SCB) over multiple field seasons spanning 3 years. Clicks, click trains, and pulsed calls were counted and classified based on acoustic measurements, leading to the identification of 19 key call features used for analysis. Kruskal-Wallis tests indicated that call features differ significantly across behavioral categories. Previous work had discovered two distinctive click Types (A and B), which may correspond to known subpopulations of Pacific white-side dolphins in the Southern California Bight; this study revealed that animals producing these different click types also differ in both their behavior and vocalization patterns. Click Type A groups were predominantly observed slow traveling and milling, with little daytime foraging, while click Type B groups were observed traveling and foraging. These behavioral differences may be characteristic of niche partitioning by overlapping populations; coupled with differences in vocalization patterns, they may signify that these subpopulations are cryptic species. Finally, random forest decision trees were used to classify behavior based on vocalization data, with rates of correct classification up to 86%, demonstrating the potential for the use of vocalization patterns to predict behavior.
对南加州湾（SCB）的太平洋白边海豚进行了多次野外调查，记录了其表面行为和同期水下发声。根据声学测量，对 clicks、click trains 和 pulsed calls 进行了计数和分类，确定了 19 个关键的叫声特征用于分析。Kruskal-Wallis 检验表明，叫声特征在行为类别之间存在显著差异。先前的研究发现了两种不同的 click Type（A 和 B），这可能对应于南加州湾已知的太平洋白边海豚亚群；本研究表明，产生这些不同 click type 的动物在行为和发声模式上也存在差异。Click Type A 组主要观察到缓慢游动和游动，白天觅食活动较少，而 Click Type B 组观察到游动和觅食。这些行为差异可能是重叠种群的生态位分化的特征；再加上发声模式的差异，这可能表明这些亚群是隐种。最后，随机森林决策树被用于根据发声数据对行为进行分类，正确分类率高达 86%，这表明发声模式有潜力用于预测行为。
