Blue whales are very rarely seen in the Southern Ocean and yet by using this technology scientists on a seven-week voyage to the Southern Ocean were able to collect 57 photo identifications, 23 biopsy samples and attach satellite tags to two of these colossal whales.
Environment Minister Tony Burke said the researchers, working from small boats in freezing Antarctic conditions, were entertained and captivated by the remarkable behaviour of the blue whales they encountered.
Mr Burke said the achievements of this non-lethal research method clearly show it is not necessary to kill whales in order to study them.
“The Antarctic blue whale can grow to over 30 metres in length and weigh up to 180 tonnes, its tongue alone is heavier than an elephant and its heart is as big as a small car. Even the largest dinosaur was smaller than the blue whale,” Mr Burke said.
“The Antarctic blue whale barely escaped extinction during the industrial whaling era in the 1900’s when around 340,000 whales were slaughtered,” Mr Burke said.
“This research reinforces Australia’s commitment to non-lethal research of whales.”
The voyage was the inaugural Southern Ocean trip of the Antarctic Blue Whales Project, which aims to estimate the abundance, distribution and behaviour of this iconic species.
The 18-strong science team of acousticians, engineers, whale tagging experts and observers deployed passive acoustic sonobuoys west of the Ross Sea area to locate the blue whales.
Lead marine mammal acoustician, Dr Brian Miller, said Antarctic blues have a very deep and resonating song which can be picked up hundreds of kilometres across the Southern Ocean.
“The acousticians made 626 hours recordings in the sample area, with 26,545 calls of Antarctic blue whale analysed in real time. The researchers were then able to triangulate the position of the whales from their vocalisations and direct the ship to the target area,” Dr Miller said.
“A team in a small boat was then deployed to gather skin biopsies and photo identifications from the whales,” he said.
Whale tagger, Dr Virginia Andrews-Goff, said the researchers were able to deploy satellite tags on two blue whales.
“The tags transmitted never-before obtained data on rapid longitudinal movements during their summer feeding season and their foraging behaviour in relation to the edge of the Antarctic ice,” Dr Virginia Andrews-Goff said.
“This method of studying Antarctic blue whales has been so successful it will now become the blueprint for other whale researchers across the world.”
On the voyage the scientists made a total of 720 cetacean sightings, including humpback, minke, fin and bottle-nosed whales, as well as collecting environmental data and Antarctic krill samples.
The Antarctic Blue Whales Project is a flagship program of the international Southern Ocean Research Partnership involving ten countries — Argentina, Australia, Brazil, Chile, France, Germany, New Zealand, Norway, South Africa and the United States.
The results from this voyage will be shared with the International Whaling Commission to assist in the conservation and recovery of the Antarctic blue whale.