Baumann-Pickering Simone, Wiggins Sean M, Roth Ethan H, Roch Marie A, Schnitzler Hans-Ulrich, Hildebrand John A
Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0205, USA.
J Acoust Soc Am. 2010 Jun;127(6):3790-9. doi: 10.1121/1.3409478.
Acoustic recordings from Palmyra Atoll, northern Line Islands, central Pacific, showed upsweep frequency modulated pulses reminiscent of those produced by beaked whales. These signals had higher frequencies, broader bandwidths, longer pulse durations and shorter inter-pulse intervals than previously described pulses of Blainville's, Cuvier's and Gervais' beaked whales [Zimmer et al. (2005). J. Acoust. Soc. Am. 117, 3919-3927; Johnson et al. (2006). J. Exp. Biol. 209, 5038-5050; Gillespie et al. (2009). J. Acoust. Soc. Am. 125, 3428-3433]. They were distinctly different temporally and spectrally from the unknown beaked whale at Cross Seamount, HI [McDonald et al. (2009). J. Acoust. Soc. Am. 125, 624-627]. Genetics on beaked whale specimens found at Palmyra Atoll suggest the presence of a poorly known beaked whale species. Mesoplodon sp. might be the source of the FM pulses described in this paper. The Palmyra Atoll FM pulse peak frequency was at 44 kHz with a -10 dB bandwidth of 26 kHz. Mean pulse duration was 355 mus and inter-pulse interval was 225 ms, with a bimodal distribution. Buzz sequences were detected with inter-pulse intervals below 20 ms and unmodulated spectra, with about 20 dB lower amplitude than prior FM pulses. These clicks had a 39 kHz bandwidth (-10 dB), peak frequency at 37 kHz, click duration 155 mus, and inter-click interval between 4 and 10 ms.
来自中太平洋莱恩群岛北部帕尔米拉环礁的声学记录显示，频率上调的调频脉冲让人联想到突吻鲸发出的脉冲。这些信号的频率更高、带宽更宽、脉冲持续时间更长，且脉冲间隔比之前描述的布兰氏突吻鲸、柯氏突吻鲸和热尔韦氏突吻鲸的脉冲更短[齐默等人（2005年）。《美国声学学会杂志》117卷，3919 - 3927页；约翰逊等人（2006年）。《实验生物学杂志》209卷，5038 - 5050页；吉莱斯皮等人（2009年）。《美国声学学会杂志》125卷，3428 - 3433页]。它们在时间和频谱上与夏威夷十字海山的未知突吻鲸明显不同[麦克唐纳等人（2009年）。《美国声学学会杂志》125卷，624 - 627页]。在帕尔米拉环礁发现的突吻鲸标本的遗传学研究表明，存在一种鲜为人知的突吻鲸物种。中喙鲸属物种可能是本文所描述的调频脉冲的来源。帕尔米拉环礁调频脉冲的峰值频率为44千赫，-10分贝带宽为26千赫。平均脉冲持续时间为355微秒，脉冲间隔为225毫秒，呈双峰分布。检测到脉冲间隔低于20毫秒且频谱未调制的嗡嗡声序列，其幅度比之前的调频脉冲低约20分贝。这些咔嗒声的带宽为39千赫（-10分贝），峰值频率为37千赫，咔嗒声持续时间为155微秒，咔嗒声间隔在4至10毫秒之间。
