Rescuers are continuing their search fora humpback whalethat was spotted entangled in a drum line off Sydney’s coast and appeared to be moving south, but authorities also say the mammal may free itself.
The NSW National Parks and Wildlife Service (NPWS) had been tracking the eight-metre whale after its pectoral fin was seen entangled 1km off the coast of Newcastle on Saturday.
The whale appeared to resurface off the northern beaches inSydneyon Sunday, and then disappeared from sight while swimming around the south head of Sydney.
“Given the nature of the entanglement, the animal may disentangle itself,” a spokesperson for NPWS said.
Vanessa Pirotta, a wildlife scientist, said it’s not yet clear what the drum line which the whale is entangled in was used for.
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Drum lines, which have fishing lines attached to a buoy, can be used for fishing or to catch and divert sharks away from popular swimming areas.
She said it’s also unclear if the whale – which should be heading north as part of its migration pattern – had swum south due to distress caused by the entanglement.
Theannual procession of thousands of whales that migratefrom Antarctic feeding grounds to tropical breeding areas along Australia’s east and west coasts began this month.
“Animal behaviour is unpredictable, and it’s hard to tell how long it has been entangled for,” Pirotta said.
“Looking for an entangled whale is like looking for a needle in a hay stack. It may be the size of a bus, but the ocean is a big place.”
The Organisation for the Rescue and Research ofCetaceans(Orrca) believed the whale was travelling south on Monday, but the animal’s movements and difficult weather conditions had made tracking it more difficult.
Pip Jacobs, a spokesperson for Orrca, said the whale’s speed had been erratic, possibly because it is stressed.
“We have Orrca members who are in this area attempting to relocate the whale this morning (by drone and from land), however predicted strong winds may make this difficult,” she said.
It is calling for New South Wales residents to keep an eye on the waves today to help track the whale.
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Orrca and the NPWS were working alongside the Department of Primary Industry Fisheries and NSW Marine Rescue to track the whale.
“The NPWS has Large Whale Disentanglement teams on standby to respond if the animal is sighted, however sea conditions will be a consideration in whether or not it is safe to attempt a disentanglement if required,” a spokesperson said.
“NPWS reminds people that for their own safety, as well as the safety of this animal, there is a 100-metre exclusion zone for recreational vehicles on water and drones in the air.”
Once hunted to near extinction, the humpback whale–Megaptera novaeangliae– have made a remarkable recovery. The whales are no longer considered threatened and population estimates now range between a healthy 30,000 to 50,000.
Animals Australia has been calling for the end of the use drum lines alongside shark nets arguing they threaten marine life. The group has beenurging the governmentto instead implement measures to protect beach-goers that are “non-lethal” to marine wildlife.
Orrca are urging anyone who spots the whale to call its 24/7 rescue hotline on (02) 9415 3333.