The Abbott government has been accused of backing away from its international obligations on animal conservation after it declared it would opt out of protecting five shark species.
Australia is submitting a "reservation" to ensure a recent international listing granting protection status to three species of thresher shark and two species of hammerhead does not take effect in Australian waters.
Humane Society International has described the move as an "unprecedented act of domestic and international environmental vandalism".
The Convention on the Conservation of Migratory Species of Wild Animals gave new protection status to 31 migratory species at a conference in November.
The listings were agreed to by consensus, with Australia among the countries present for the talks.
But the government has had a change of heart and is seeking to opt out of co-operating with other countries to protect five of the shark species, arguing that Australia already has sufficient protections in place and the listing would have unintended consequences for fishers.
Alexia Wellbelove, senior program manager at Humane Society International, said the government was responding to complaints from recreational fishers who catch and release the sharks, and commercial fishers who can accidentally trap them while hunting for other fish.
If the five shark species were given international protection status, Australian laws would kick in, making it an offence to kill, injure, take or move the species in Australian waters.
The listings were due to take effect next month.
"We just think it's really unbelievably disappointing because Australia has always led the way on shark conservation and this is really a step backward," Ms Wellbelove said.
"It's a very sad day for protection of the marine environment if we take the easy road and opt of these things, rather than taking steps to protect our domestic waters."
In a letter to Human Society International, Environment Minister Greg Hunt said Australia already had "strong domestic measures in place" for the five shark species in question but this did "not negate our support for international action related to these species, or for shark conservation more broadly".
Nine other migratory species given listings at the convention can be found in Australia and the protection status will apply.
Mr Hunt said Australia was seeking a reservation for the five shark species because a listing would have unintended consequences for fishers as a result of Australia's laws being tougher than required by the convention.
"Not doing so could see recreational fishers being fined up to $170,000 and face 2 years in jail, even when fishing in accordance with their permits," he said.
"There are still strong measures in place to protect thresher and hammerhead sharks in Australia and these will continue.
"The Australian government will continue to actively participate in shark conservation under the convention as a signatory of the Memorandum of Understanding on the Conservation of Migratory Sharks, and through $4.6 million funding for shark research and conservation activities."
