Weddell seal call types made by males and females.

Recordings were made of adult male and female Weddell seals on the ice during the breeding seasons of 1990 and 1997. The recordings were made near Davis, Antarctica in the Vestfold Hills. The vocalisations made with both the mouth and nostrils closed were classified into call types. These call types are also produced by the seals when underwater. The call classifications were based on those described by Thomas, J.A. and Kuechle,, V.B. (1982, J. Acoust. Soc. Amer. 72: 1730-1738) and Pahl, B.C., Terhune, J.M. and Burton, H.R. (1997, Aus. J. Zool. 45: 171-187). Nineteen call types were identified. Of these, males made 18 and females made 15. Trills are only made by males and it is likely that a stepped ascending whistle is only made by females. A roar and mew are also potential male-only call types. The data suggest that the Trill vocalisations can be used to indicate the presence of males. This will be useful when recording underwater where the calling seals cannot be observed directly.A description of the types of calls made by Weddell Seals is listed below.SymbolNameDescriptionOToneConstant-frequency, predominantly sinusoidal call.LGrowlConstant-frequency, broad bandwidth, long call.QWhoopConstant-frequency call with a terminal upsweep.SSqueakBrief call with constant frequency or rising frequency and an irregular waveform.WAWhistle AscendingAscending frequency, sinusoidal waveform.TCTrill Constant-FrequencyNarrow bandwidth trill with a constant-frequency beginning, sinusoidal or frequency-modulated waveform.TTrillNarrow to broad bandwidth, containing a frequency downsweep, greater than 2 seconds.WDWhistle DescendingDescending frequency, sinusoidal waveform (less than 2 seconds).MMewAbruptly descending frequency followed by a long constant-frequency ending.CChugAbruptly descending frequency followed by a brief constant-frequency ending.GGuttural Glug (Grunt)Descending-frequency call that was lower than a Chug and had a brief duration.WAGWhistle Ascending - GruntBrief Ascending Whistle followed by a Guttural Glug (Grunt), the two types alternate in a regular pattern.KKnockAbrupt, brief-duration broadband sound

本数据集于1990年与1997年的繁殖季，在南极洲维斯托尔德丘陵（Vestfold Hills）的戴维斯（Davis）科考站附近冰层上，录制成年雌雄威德尔海豹（Weddell seals）的声学信号。本次录制的是海豹闭口且闭鼻孔时发出的鸣叫声，并将其归类为不同的鸣叫声型。这些鸣叫声型同样可在海豹水下活动时被观测到。本次鸣叫声型分类参考了Thomas, J.A.与Kuechle, V.B.（1982年，《美国声学学会杂志》，第72卷，1730-1738页）以及Pahl, B.C.、Terhune, J.M.与Burton, H.R.（1997年，《澳大利亚动物学杂志》，第45卷，171-187页）提出的分类标准。本次研究共识别出19种鸣叫声型：其中雄性海豹可发出18种，雌性海豹可发出15种。颤音（Trill）仅由雄性海豹发出，而阶梯式上升哨声大概率仅为雌性特有；低吼（Roar）与喵叫（Mew）也被推测为雄性专属鸣叫声型。数据表明，颤音（Trill）鸣叫声可用于指示雄性威德尔海豹的存在，这一点在水下录音场景中尤为实用——此时无法直接观测到正在发声的海豹个体。威德尔海豹鸣叫声型的详细描述如下：
O 单音（Tone）：以恒频为主的类正弦波形鸣叫声。
LG 低吼（Growl）：恒频、宽频带的长时长鸣叫声。
Q 长鸣（Whoop）：带有终端上扫的恒频鸣叫声。
S 尖鸣（Squeak）：时长较短的恒频或升频鸣叫声，波形不规则。
WA 上升哨声（Whistle Ascending）：频率随时间上升的正弦波形鸣叫声。
TC 恒频颤音（Trill Constant-Frequency）：窄频带颤音，起始段为恒频，波形为正弦或调频形式。
T 颤音（Trill）：频带宽度由窄至宽，包含频率下扫过程，时长超过2秒。
WD 下降哨声（Whistle Descending）：频率随时间下降的正弦波形鸣叫声（时长小于2秒）。
M 喵叫（Mew）：频率先骤降，随后伴随长时恒频收尾段的鸣叫声。
C 重击声（Chug）：频率先骤降，随后伴随短时恒频收尾段的鸣叫声。
G 喉音咕嘟声（Guttural Glug/Grunt）：频率随时间下降的低频鸣叫声，相较于重击声（Chug）音调更低，且时长较短。
WAG 上升哨声-咕嘟声组合（Whistle Ascending - Grunt）：由一段短时上升哨声与一段喉音咕嘟声交替组成的规整鸣叫声型。
K 敲击声（Knock）：突发、短时的宽带声响。