EFESydney

A group of scientists from Australia and New Zealand plan to place sonobuoys in the Antarctic waters to track the elusive blue whale (Balaenoptera musculus), scientific sources reported Tuesday.

"Finding blue whales is a bit like looking for a needle in a haystack, but we have a secret - we're going to listen for them," said lead scientist Richard O'Driscoll of the National Institute of Water and Atmospheric Research in New Zealand, which is undertaking this study with the Australian Antarctic Division.

The scientists Wednesday begin their six-week journey aboard research vessel Tangaroa to the Balleny Islands, in the Antarctic Ocean, to study blue whales as well as humpback whales (Megaptera novaeangliae) and the Antarctic toothfish (Dissostichus mawsoni).

"The Balleny Islands are known as a feeding hotspot for humpbacks but little is known about what they eat," O'Driscoll said.

"Commercial whaling almost wiped out the blue whales, however there are signs they are now starting to come back," he added.

As a part of the study, the scientists are to place sonobuoys to capture low-frequency sounds emitted by whales, according to a statement by the Australian Antarctic Division.

"Crossed bearings from multiple sonobuoys will accurately pinpoint the location of the whales," said Australian scientist Mike Double, who hopes to uncover the reason behind blue whales gathering in feeding hotspots around the Antarctic.

The scientists will also visit toothfish fishing grounds in the Ross Sea to study the abundance and distribution of their main prey such as icefish and grenadiers.

They will also install sonar equipment in Terra Nova Bay which has a large concentrations of Antarctic silverfish larvae (Pleuragramma antarticum), an important food source for birds, fish, whales and other marine animals.

"When the ice clears in spring, you find lots of eggs and larvae of silverfish but you don't see the adults. We don't know if the adults move in during winter and lay their eggs there, or if the eggs drift in from somewhere else," O'Driscoll said.