Regional dialects and herd formation aspects of Weddell seal (Leptonychotes weddellii) underwater vocalisations.

Database Description

The files represent the 41 different Weddell seal (Leptonychotes weddellii) call types identified at either Mawson, Davis, and/or Casey. They were collected between 60 degrees 49' E and 110o 40' E in longitude, and between 66 degrees 12' S and 68 degrees 34' S in latitude. Each call type name includes two elements. The first is a three-digit number starting at 301 to identify the call type. The second is a one to three-letter code referring to the call category that each type falls into. The 13 different possible call categories are:

SymbolNameDescription
OToneConstant-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

(from: Pahl, B.C., Terhune, J.M. and Burton, H.R. 1997).

The 41 call types were divided into two sections, the first 33 (301-O to 333-K) being common call types and the last 8 (334-Q to 341-WD) being rare call types. In each call type folder, one to five different samples of each call type are provided. They are identified by a small case letter added at the end of the call type name. Each sample includes both a .WAV audio sample and a .JPG image of the call type spectrogram showing call shape, i.e., changes in call frequency (vertical) over time (horizontal). These call types were used to identify: (a) unique call types or call categories, (b) differences in call type or call category usage (the frequency of occurrence of each call type or category), and (c) differences in call features (number of elements, start frequency, frequency shift and first element duration) among the three stations.

The download file also includes a spreadsheet of data and a text file explaining how to interpret the data.

Analysis of this dataset is ongoing.

数据集说明
本数据集收录了分别在莫森站、戴维斯站及/或凯西站识别得到的41种不同威德尔海豹（Leptonychotes weddellii）鸣声类型。数据采集区域的经度范围为东经60°49′至110°40′，纬度范围为南纬66°12′至68°34′。

每种鸣声类型的名称包含两个组成部分：其一为以301为起始的三位数字编号，用于标识该鸣声类型；其二为1至3位的字母代码，用以指明该鸣声所属的类别。共计13种不同的鸣声类别，具体如下：
1. O 单音（Tone）：恒定频率、以正弦波为主的鸣声；
2. L 低吼（Growl）：恒定频率、宽带宽、长时长鸣声；
3. Q 啸叫（Whoop）：带有终端上扫频的恒定频率鸣声；
4. S 尖啸（Squeak）：时长较短，频率恒定或呈上升趋势，波形不规则的鸣声；
5. WA 上升哨声（Whistle Ascending）：频率随时间上升的正弦波形鸣声；
6. TC 恒定频率颤音（Trill Constant-Frequency）：起始段为恒定频率的窄带宽颤音，波形为正弦波或调频波形；
7. T 颤音（Trill）：带宽范围从窄到宽，包含频率下扫频，时长超过2秒的鸣声；
8. WD 下降哨声（Whistle Descending）：频率随时间下降的正弦波形鸣声，时长小于2秒；
9. M 喵叫（Mew）：频率先骤降，随后以长时段恒定频率收尾的鸣声；
10. C 低哼（Chug）：频率先骤降，随后以短时段恒定频率收尾的鸣声；
11. G 喉音咕哝（Grunt，Guttural Glug）：频率呈下降趋势的短时长鸣声，其频率低于低哼（Chug）；
12. WAG 上升哨声-哼鸣组合（Whistle Ascending - Grunt）：由短暂的上升哨声与喉音咕哝交替组成的鸣声，二者呈现规律的交替模式；
13. K 敲击声（Knock）：短促、陡峭的宽带声音。

（数据来源：Pahl, B.C.、Terhune, J.M. 与 Burton, H.R.，1997年）

本次收录的41种鸣声类型被划分为两类：前33种（编号301-O至333-K）为常见鸣声类型，后8种（编号334-Q至341-WD）为稀有鸣声类型。

每个鸣声类型的文件夹中，均提供1至5份该类型的鸣声样本，样本以追加在鸣声类型名称末尾的小写字母进行区分。每份样本均包含一份.WAV格式的音频文件，以及一张展示鸣声波形的语谱图（spectrogram）.JPG图像，该图像可体现鸣声频率（纵轴）随时间（横轴）的变化情况。

本数据集的41种鸣声类型可用于以下三类研究：(a) 识别独特的鸣声类型或鸣声类别；(b) 分析不同站点间鸣声类型/类别的使用差异（即各鸣声类型或类别的出现频率）；(c) 分析不同站点间鸣声特征的差异，包括鸣声元素数量、起始频率、频率偏移及首个元素的持续时长。

下载包中还包含一份数据电子表格，以及一份用于说明数据解读方法的文本文件。

本数据集的相关分析工作仍在进行中。