TOWNSVILLE – Sharks found in shallow, tropical waters around northern Australia are well placed to cope with climate change, according to Queensland researchers.

With scientists warning climate change could warm and acidify the oceans as well as lower oxygen levels, any shift could be disastrous for marine ecosystems.

But Townsville-based marine scientist Jodie Rummer has discovered the tiny epaulette carpet shark found across northern Australia and New Guinea is likely to thrive.

For her research investigating sharks, Dr Rummer has been awarded a prestigious United Nations fellowship to expand her work at the world’s largest shark sanctuary in French Polynesia.

“The epaulette shark lives in shallow reefs, reef flats, within the coral in a lot of cases where it can experience dramatic fluctuations in temperature and oxygen levels,” Dr Rummer said.

“Because of its small size, because it doesn’t have a particularly big bite like other sharks do, so it uses these habitats for protection.

“It does so very well in terms of low oxygen, it’s the best of all sharks that we know.

“It can also tolerate high CO2 conditions as well – levels that we’re expecting to occur in our oceans by the end of the century and these sharks are neither physiologically nor behaviourally affected by those levels.”

Dr Rummer has investigated how fish deliver oxygen to their tissues and said they were 25 to 50 times better than humans.

She believes the epaulette sharks have adapted to the tough, shallow conditions over time.

“We think that it’s because they’re a product of their environments – they experience these conditions very often and so they have to have those mechanisms inside their body to cope with the low oxygen and high carbon dioxide,” she said.

The L’Oreal-UNESCO For Women in Science fellowship will allow Dr Rummer to expand her research to Moorea in French Polynesia to find out how other sharks are likely to respond to climate change.

There she will study sicklefin lemon sharks and black-tip reef sharks which may be less able to adapt to future ocean conditions.

“I’ve been working with a team of French scientists that have identified 15 sites around the island of Moorea that the mother sharks come in to pup the babies and they basically release the babies in these shallow areas,” Dr Rummer said.

“That gives us 15 sites around the island where we have access to these baby sharks that are about 55 centimetres or so and they’re living in these shallow habitats so we can track them.

“We can monitor changes in their blood chemistry, how they’re using oxygen, the changes they’re making when they venture into warmer temperatures, how fast they’re using food, how much energy it takes them to use food and the types of habitats that they prefer to be in to start to understand the picture.”

“The point of taking my research to investigate these additional species is to identify the species that might be in most trouble from climate change – and then why they might be in most trouble,” Dr Rummer said.

“Are they trying to use some of the same mechanisms that the species that are doing well use on a daily basis?

“How can we predict how changes in their habitats will affect where they live? How they use energy? How they’re able to get oxygen into their body to deliver it to muscles to enable it to swim around?”

Dr Rummer hopes what she learns from the sharks will ultimately benefit communities reliant on fishing.

“Being sharks, they are key to a healthy ecosystem– they’re the top predator in many ecosystems in many communities and if you remove a predator as we know from so many world examples, the entire ecosystem is disrupted,” she said.

“Especially for Pacific Island communities that may be depending on fish and marine life for their only source of protein – there could be dire consequences for these communities if they start to lose ecosystem health and healthy fishes.”

While her previous research has been with the far more timid epaulette sharks which don’t bite, her work in Moorea may not be as painless.

“The sharks that I’m working with in Moorea, there’s a bit more of a challenge with avoiding the teeth – so far my male colleagues have gotten bitten but I haven’t, so touch wood on that.

“They’re kind of like little puppy dogs in that respect – they’ve got the teeth, they just don’t know what to do with them just yet.”