02008nas a2200181 4500008004100000245008500041210006900126490000600195520141700201653002601618653002401644653003201668653002201700653001701722100002301739700002301762856004101785 2022 eng d00aMid-frequency song and low-frequency calls of sei whales in the Falkland Islands0 aMidfrequency song and lowfrequency calls of sei whales in the Fa0 v93 a
Although sei whales (Balaenoptera borealis) are distributed throughout the globe, their behaviour and vocal repertoire are poorly described. We used passive acoustic monitoring to describe the vocal behaviour of sei whales in the Falkland Islands, between December 2018 and April 2019. We isolated more than 2000 low-frequency calls for manual classification, of which 510 calls with high signal-to-noise ratio were quantitatively measured. Five categories of stereotyped call types in the 15–230 Hz range were described, some with multiple subcategories. These included some similar to previously described calls (e.g. downsweeps), but others that were novel in acoustic structure and frequency band. In the mid-frequency range, we documented a highly stereotyped, hierarchically structured and rhythmically repetitive song display. Songs were arranged in phrases with a structure composed of repetitive sub- phrases, and a diverse variety of sounds in the 1–5 kHz range. Singing commenced in late February, despite the presence of whales and calls since early December, and continued through April. These acoustic properties and behavioural characteristics indicate that this is likely a male breeding display similar to songs and singing of other balaenopterids. This is the first detailed description of a song display for sei whales, highlighting the importance of the Falkland Islands.
10aBalaenoptera borealis10alow-frequency calls10apassive acoustic monitoring10asinging behaviour10asong display1 aCerchio, Salvatore1 aWeir, Caroline, R. uhttps://bio.acousti.ca/ja/node/58484