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

Brief description

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.

Lineage

Progress Code: completed

Statement: The sound files are in the .WAV format. The images are .JPEG and are sound spectrographs of the accompanying .WAV file and weremade using various frequency and analyzing bandwidths using Spectrogram by R.S. Horne.