![]() This finding allows the interpretation of a wealth of long-term acoustic recordings for this previously acoustically concealed species, which will improve our understanding of the distribution, abundance and behaviour of Antarctic minke whales. We analysed data from multi-sensor acoustic recording tags that included intense bio-duck sounds as well as singular downsweeps that have previously been attributed to this species. Here, we present conclusive evidence that the bio-duck sound is produced by Antarctic minke whales (Balaenoptera bonaerensis). Heard mainly during austral winter in the Southern Ocean, this ubiquitous sound has been recorded in Antarctic waters and contemporaneously off the Australian west coast. Mysterious bio-duck sound attributed to the Antarctic minke whale (Balaenoptera bonaerensis), Biology Letters, Published 23 April 2014 DOI: 10.1098/rsbl.2014.0175įor decades, the bio-duck sound has been recorded in the Southern Ocean, but the animal producing it has remained a mystery. One is that they are a primary target of Japanese whalers, the other is because of where they live-a part of the ocean undergoing transformation due to global warming. Research on the minke whales is particularly important for two reasons. The researchers note that solving the mystery is more than fanciful, now that the source is known, researchers can use recording equipment to track their migration, feeding patterns or even the reproduction cycles of the whales, offering the possibility of a whole new research area. Recordings made of this and one other animal revealed that minke whales are the source of the mysterious and strange "bio-duck" sound that is common in the Southern Ocean. The suction cup tag detaches after a number of hours, then researchers retrieve the tag to download the data. The small green tag attached to this whale records depth, heading, and roll, and also has a microphone that records the sounds made by the animal and other sounds in the environment. ![]() One of two minke whales that researchers from Duke University outfitted with a suction cup tag. ![]() The recordings were compared to prior recordings of bio-duck sounds made by researchers aboard submarines and were found to match, solving the mystery of the bio-duck sounds. A sensor on one of the whales gave away the secret of bio-duck sounds-capturing the distinctive bio-duck noise, repeating several times as the whale was near the surface. The sensors they used were quite sophisticated, yet small-they capture and record not only sound, but water depth and movements in 360 degrees-plus, they don't cause harm, they're held on by suction cups. Thus it was a bit of a triumph that the team was able to manage to do so. Putting sensors on minke whales is not easy-they're fast and turn on a dime. In this latest effort, the researchers took a direct approach-they attached sensors to the backs of two of the whales and captured data for 24 hour periods. Since that time, many scientists have heard and captured the noises, though until now, no one really knew from whence they came. Press.Reports of seasonal bio-duck sounds have circulated since the 1960's, when they were first reported by personnel aboard submarines. "Social behavior and pairing chronology of Mottled Ducks during autumn and winter in Louisiana." In Waterfowl in winter., edited by M. A single sharp whistle (the Burp) is given by males during the Head-up-tail-up Display, and males give a Grunt-whistle (see Behavior: sexual) during courtship ( Johnsgard 1965 An irregularly accented Gagg note is given by females during the Inciting display, while a Gaeck-gaeck-gaeck-gaeck call may be heard during the Gesture-of-repulsion Display (see Behavior: sexual). When alarmed, females emit 3-4 harsh Quacks they emit a muffled Tickety-tickety-tickety while feeding and sometimes while in flight. Females have loud, raspy, sequenced Decrescendo Call ( Quack), which typically consists of 6 notes, with the second note being the loudest and highest in pitch ( Johnsgard 1965 ![]() Cornell University Press, Ithaca, NY, USA. Males emit low, raspy, Raeb a single Raeb is given as an alarm call, while a two-note Raeb-raeb may be given during courtship or as a conversational call ( Johnsgard 1965 Mottled Duck vocalizations generally resemble those of the Mallard.
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