Review of Underwater and In-Air Sounds Emitted by Australian and Antarctic Marine Mammals

Abstract

The study of marine soundscapes is a growing field of research. Recording hardware is becoming more accessible; there are a number of off-the-shelf autonomous recorders that can be deployed for months at a time; software analysis tools exist as shareware; raw or preprocessed recordings are freely and publicly available. However, what is missing are catalogues of commonly recorded sounds. Sounds related to geophysical events (e.g. earthquakes) and weather (e.g. wind and precipitation), to human activities (e.g. ships) and to marine animals (e.g. crustaceans, fish and marine mammals) commonly occur. Marine mammals are distributed throughout Australia's oceans and significantly contribute to the underwater soundscape. However, due to a lack of concurrent visual and passive acoustic observations, it is often not known which species produces which sounds. To aid in the analysis of Australian and Antarctic marine soundscape recordings, a literature review of the sounds made by marine mammals was undertaken. Frequency, duration and source level measurements are summarised and tabulated. In addition to the literature review, new marine mammal data are presented and include recordings from Australia of Omura's whales (Balaenoptera omurai), dwarf sperm whales (Kogia sima), common dolphins (Delphinus delphis), short-finned pilot whales (Globicephala macrorhynchus), long-finned pilot whales (G. melas), Fraser's dolphins (Lagenodelphis hosei), false killer whales (Pseudorca crassidens), striped dolphins (Stenella coeruleoalba) and spinner dolphins (S. longirostris), as well as the whistles and burst-pulse sounds of Australian pygmy killer whales (Feresa attenuata). To date, this is the most comprehensive acoustic summary for marine mammal species in Australian waters.

Global Distribution of Omura’s Whales (Balaenoptera omurai) and Assessment of Range-Wide Threats

“…Review of the IMOS recordings indicated presence of these vocalizations during 7 of 11 months at Pilbara and 10 of 11 months at Kimberley region between November 2012 and September 2013. Independently, 17 https://acoustic.aodn.org.au/acoustic/ Erbe et al (2017) also attributed these same signals to Omura's whales based upon comparison to spectrograms and acoustic characteristics reported in Cerchio et al (2015), stating that they are frequently recorded on Australia's Northwest Shelf and were accompanied by photographic evidence of Omura's whales, but report no detail on location(s). McCauley (2009) was the first to report on these vocalizations, attributing them to Bryde's whales before the description of Omura's whale song by Cerchio et al (2015) and the attribution of Erbe et al (2017); song was documented across an extensive range from at least ten recording sites in the waters between Exmouth (21.58 • S 113.90 • E) to north of Darwin (approximately 9.5 • S 129 • E).…”

“…Independently, 17 https://acoustic.aodn.org.au/acoustic/ Erbe et al (2017) also attributed these same signals to Omura's whales based upon comparison to spectrograms and acoustic characteristics reported in Cerchio et al (2015), stating that they are frequently recorded on Australia's Northwest Shelf and were accompanied by photographic evidence of Omura's whales, but report no detail on location(s). McCauley (2009) was the first to report on these vocalizations, attributing them to Bryde's whales before the description of Omura's whale song by Cerchio et al (2015) and the attribution of Erbe et al (2017); song was documented across an extensive range from at least ten recording sites in the waters between Exmouth (21.58 • S 113.90 • E) to north of Darwin (approximately 9.5 • S 129 • E). McCauley (2009McCauley ( , 2014 reports year-round presence of these song phrases from at least The first known account in Australia is also the most southern record for the species, a stranding of a 10.2 m individual of unknown sex in January 2000 at Black Point, Yorke Peninsula, Gulf St Vincent, South Australia, near Adelaide (Yamada et al, 2006b;Kemper, personal communication to TKY).…”

Non-song Vocalizations of Humpback Whales in Western Australia

“…Many studies use onomatopoeic names to describe sounds. This method can be problematic for comparison because sounds may be assumed similar or different depending on the perception of the analyst (Dunlop et al, 2007;Erbe et al, 2017). Here, a comparison of spectrograms showed similarities among multiple sounds in different studies, some of which were given a different onomatopoeic name ( Table 5).…”

“…According to spectrographic features, baleen whale sounds can be classified as constant-wave (CW), frequency-modulated (FM), or amplitude-modulated (AM) (Erbe et al, 2017). However, in the literature, these are frequently named and grouped according to how they are perceived by human listeners (and are given onomatopoeic names, such as grunt, growl, moan, wop, etc.).…”

“…However, in the literature, these are frequently named and grouped according to how they are perceived by human listeners (and are given onomatopoeic names, such as grunt, growl, moan, wop, etc.). While most of the published studies that describe humpback whale vocalizations use onomatopoeic names, this type of classification may be problematic because different authors may give different names to the same signals, making a direct comparison difficult (Cholewiak et al, 2013;Erbe et al, 2017). Spectral features, however, are more standard and facilitate comparison among different signals, although some variation in categorization can occur as a result of recording and analysis settings (Erbe et al, 2017).…”