2 Blue whales given satellite tags in the Antarctic

22/03/2013 09:30:36 New acoustic devices prove successful for tracking Blue whales
March 2013. A recent research expedition to the Antarctic, using acoustic devices to locate Blue whales, has proved very successful. By using sound rather than sight to initially detect the whales, scientists significantly improved the likelihood of finding and counting whales in the vast Southern Ocean. The research is a core part of an Australian-led international project to estimate the abundance, distribution and behaviour of the species that was decimated in the early 1900s when industrial whaling killed approximately 250,000 animals.

The sonobuoys allowed researchers to record more than 500 hours of audio including more than 20,000 blue whale vocalisations. Two Blue whales were given satellite tags to enable scientists to track their migration, which, it is hoped, will provide vital information on their behaviour and biology.

The 2013 expedition achievements included:

• 626 hours of acoustic recordings in the sample area; 26,545 calls of Antarctic blue whale were analysed in real time; 43 acoustic groups were targeted, with an 85% success rate.
• Identification of 57 individual Antarctic blue whales using photos, plus 11 pygmy blue whales. Identification of 23 individual Antarctic blue whales using biopsy samples, plus 8 humpback whales.
• Satellite tags on 2 Antarctic blue whales; both transmitting locations for more than 15 days so far.
• 100 specimens of Antarctic krill collected for genetics research.

Non-lethal techniques
These statistics do not tell the whole story. Importantly this voyage demonstrated a suite of non-lethal techniques, including acoustic tracking, satellite tagging, photographic and genetic identification, which can be used to study the elusive Antarctic blue whales. The information gathered on this voyage will go towards answering the big question about just how many of these animals remain in the oceans today.

The Once the ship has reached New Zealand, the real work begins in analysing the huge data set collected over the past seven weeks.

A spokesman for the crew said "The offices we go back to won't heave with each wave and the outlook will be less exhilarating, but the work will be equally satisfying and worthwhile. Papers have to be prepared for the International Whaling Commission meeting in Korea in June and the methods, tested and proven on this voyage, will be communicated to our colleagues in the Southern Ocean Research Partnership."