Data from: Vocalisations of killer whales (Orcinus orca) in the Bremer Canyon, Western Australia

To date, there has been no dedicated study in Australian waters on the
acoustics of killer whales. Hence no information has been published on the
sounds produced by killer whales from this region. Here we present the
first acoustical analysis of recordings collected off the Western
Australian coast. Underwater sounds produced by Australian killer whales
were recorded during the months of February and March 2014 and 2015 in the
Bremer Canyon in Western Australia. Vocalisations recorded included
echolocation clicks, burst-pulse sounds and whistles. A total of 28 hours
and 29 minutes were recorded and analysed, with 2376 killer whale calls
(whistles and burst-pulse sounds) detected. Recordings of poor quality or
signal-to-noise ratio were excluded from analysis, resulting in 142
whistles and burst-pulse vocalisations suitable for analysis and
categorisation. These were grouped based on their spectrographic features
into nine Bremer Canyon (BC) “call types”. The frequency of the
fundamental contours of all call types ranged from 600 Hz to 29 kHz. Calls
ranged from 0.05 to 11.3 seconds in duration. Biosonar clicks were also
recorded, but not studied further. Surface behaviours noted during
acoustic recordings were categorised as either travelling or social
behaviour. A detailed description of the acoustic characteristics is
necessary for species acoustic identification and for the development of
passive acoustic tools for population monitoring, including assessments of
population status, habitat usage, migration patterns, behaviour and
acoustic ecology. This study provides the first quantitative assessment
and report on the acoustic features of killer whales vocalisations in
Australian waters, and presents an opportunity to further investigate this
little-known population.