A 46-year-old woman was mauled on Wednesday and a 12-year-old girl was attacked on Thursday while swimming from yachts in Cid Harbour on Whitsunday Island.
In response, the Queensland government has set baited drum lines in Cid Harbour to reduce the local shark numbers.
“It is possible that there’s more than one shark involved in these unfortunate events,” Fisheries Queensland manager Jeff Krause told Australian Broadcasting Corp.
“We don’t normally go out and search for any sharks that may have been involved in a shark attack, but due to the nature of these multiple attacks, Fisheries Queensland is going to deploy three drum lines in a bid to try and catch some of the sharks in that area,” he added.
The victims were in critical but stable condition with leg wounds in hospitals in the Queensland state capital, Brisbane.
The girl is from Melbourne and had been on vacation with her father and sister while the woman is from Tasmania.
Queensland Yacht Charter, which managed the victims’ yachts, said tourists had been advised to refrain from swimming near the Whitsunday Islands for the foreseeable future.
The islands attract various whaler shark species as well as bull and tiger sharks.
The last shark attack in the area was eight years ago.
Daryl McPhee, a shark expert at Bond University, said that while the likelihood of being attacked by a shark was slim, the Great Barrier Reef has a higher population of sharks than other areas.