16 August 2013
Scientists at the South Australian Museum will begin work on a Southern Right Whale recovered on southern Eyre Peninsula nearly two weeks ago.
A team sent by the Museum spent a week salvaging the whale’s skeleton and important organs, after the dead mammal was reported stranded and surrounded by sharks near Tumby Bay.
Collection Manager of Mammals David Stemmer says the Museum is pleased to have its second Southern Right Whale specimen.
“We managed to get the whole skeleton, both testes, the earplugs and tissue samples. It was everything we were hoping to get, which we’re very happy about because when you go out to a whale of such size you never quite know whether you will be fully successful or not,” he said.
Researchers had a tough job on their hands: the whale was on crown land in a difficult-to-reach location, and was stranded in the water – surrounded by great white sharks!
The team was able to eventually move the whale further up the beach with the help of a front-end loader. This more accessible position and three consecutive days of good weather enabled the team to remove most of the skeleton before the tide turned on them, threatening to pull the remaining bones out to sea. The team was battling high swells and tides for three hours before they were finally able to salvage the last remaining parts of the skeleton.
Already, the researchers have been able to garner some information from the 11.2 metre whale.
“The bones, as it turns out, were quite young and not fused. The testes that are about half a tonne in a fully-grown adult were more like half a kilo,” Mr Stemmer said, “so it was much younger than we initially thought.
“We hope to be able to learn its age from the ear plugs as they have layers, a bit like growth rings on a tree. Normally we use the teeth but in baleen whales there are none, so we use the earplugs.” The whale had a major impact on the side of its head and body which most likely would have been caused by a boat strike. There were also a lot of shark bites on the whale which were suspiciously placed in a pattern that you would expect from propeller cuts. Unfortunately, we weren’t able to find any conclusive evidence for this type of injury.
The Museum’s mammals rescue team is often called out to collect deceased whales and dolphins along South Australia’s coastline. The studies – particularly with specimens as rare as the Southern Right Whale – give a better perspective of the life cycles of these creatures and help us develop strategies to protect them.
The skeleton is now at the Museum’s Bolivar facility where it will be composted; a different method of cleaning the bones than is usually used. In the past, the Museum has macerated skeletons, which involves rotting the flesh off the bone in water.
However, Mr Stemmer has recently been in discussion with a colleague working at the Smithsonian Institute in the United States who has had good results with composting. The technique is more complicated and labour-intensive, but will hopefully produce a better quality skeleton for the Museum’s collection and research efforts.