Wednesday, 8 February 2012

Humback song







In 1967, Dr Payne and Scott McVay studied the intricate vocalisations of humpback whales. They realised that they were hearing fixed rhythmic pattern of repeated sounds or songs. Although many other whale species also sing songs and make a variety of noises, the humpback has the longest and most complex songs.

Since this discovery, Dr Payne and colleagues at Ocean Alliance have gathered songs from humpback populations throughout the world. Ocean Alliance’s Whale Song Library now contains more than 1,500 recordings from fourteen different geographic regions. The library totals more than 6,000 hours of sounds and is the largest collection of humpback recordings.
Katharine Payne discovered that all the humpback whales in a given area sing versions of the same song, which changes throughout the course of the season. Following this, Ocean Alliance scientists discovered that although humpback whales in the Atlantic, Pacific and Indian oceans follow the same rules to construct their songs, that the changes in the songs for each ocean have occurred independently of changes in other oceans (presumably singers in different oceans cannot hear each other); so that in the same year, the songs in different oceans are different from each other.
It seems, therefore, that songs can be helpful in delineating interbreeding populations of humpback whales.Ocean Alliance maintains libraries of information spanning back to the 1950′s.
Dr. Payne's discovery with colleague Scott McVay in 1967, that the eerie sounds made by the humpback whale were actually complex, recognisable songs, jumpstarted bioacoustics research. He determined that these songs often include rhyme and meter, and he developed a system for transcribing them. Recent data from the US Navy confirms Dr Payne's 1971 theory (with Douglas Webb) that some whale species make sounds that can be heard over hundreds or even thousands of miles. Recent analysis of low frequency sonar data has proven that Payne and Webb were correct - by utilising the special acoustic properties of deep water the sounds of whales can carry great distances. Such long-range signals may serve as beacons when whales are trying to find each other or their isolated breeding grounds. Unfortunately, something which is bad is that with the invention of propeller-driven vessels the subsequent noise pollution has undeniably interfered with whales' long range communication.

These spectrograms are from the VENTS programme.

These spectrograms are from the VENTS programme.
Blue Whale (West Pacific) 0-->40Hz



Blue Whale (North East Pacific) 0-->60Hz



Blue Whale (South Pacific) 0-->40Hz

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