Dolphin and whale numbers prominent in Bight

SPOTTED: A pair of southern right whales, believed to be a mother and a calf, in the Great Australian Bight. Picture: Kerstin Bilgmann
SPOTTED: A pair of southern right whales, believed to be a mother and a calf, in the Great Australian Bight. Picture: Kerstin Bilgmann

A large-scale survey conducted by researchers at Flinders University has discovered the Great Australian Bight is home to a significant number of dolphins and whales, including some endangered species.

The aerial survey, conducted in July and August of 2013, was part of the Great Australian Bight research program, where Flinders University researchers covered 2236 kilometres of transects, extending 252 kilometres from shore.

The program was funded by BP after the government urged the company to undertake an environmental assessment for drilling potential, however the company has since abandoned their plans for drilling in the Bight.

The survey was undertaken by Dr Kerstin Bilgmann, Dr Guido J Parra and associate professor Luciana Möller from the Cetacean Ecology, Behaviour and Evolution Lab and Molecular Ecology Lab at Flinders.

They found the waters off western Eyre Peninsula in South Australia were an important habitat for dolphins and whales.

Dr Bilgmann said dolphins were the most sighted cetacean species – whales, dolphins and porpoises – in the area.

“In the two weeks of flying, we sighted five cetacean species in coastal and offshore waters, including 71 schools of common dolphins and 14 schools of coastal bottlenose dolphins, as well as seven southern right whales, three humpback whales, and one minke whale.” 

She said the particularly high abundance of common dolphins in waters relatively shallow and close to the coast, known as continental shelf waters, “shows that these waters represent an important habitat for this species”. 

“The common dolphin numbers (in the Bight) are among some of the highest densities in the world of that particular species,” she said.

The second most sighted species was the bottlenose dolphin, where researchers saw the species within 12 kilometres of the shoreline, indicating they were the more coastal species of bottlenose, staying close to shallower waters. 

Sightings of endangered southern right whale included a female with a calf.

Researchers have indicated that while whales have not yet returned to certain coastal areas after 19th and 20th century whaling, they were using the region for transiting to known coastal sights such as the Head of Bight and Fowlers Bay, which was used by females for calving and nursing during winter time. 

Professor Luciana Möller said southern right whales continued to recover from past whaling, and that it was possible the region would be used more frequently by the species in the future. 

The $20 million Great Australian Bight Research Program was a collaboration between BP, CSIRO, the South Australian Research and Development Institute (SARDI), the University of Adelaide and Flinders University. 

More than 100 scientists took part in a wide range of research projects.