Humpback whale freed after long rescue mission in Sydney harbour

A humpback whale that became trapped in a rope in Sydney Harbour has been freed after a long rescue mission.

The whale became stuck in Sydney Harbour yesterday, and was located this morning after several attempts on Thursday to keep track of the tangled mammal.

The juvenile humpback whale was swimming off Bradleys Head this morning, with an exclusion zone in place as crews chased it through the harbour.

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Two boats of specialist crews freed the whale and watched as it swam back out to sea.

The whale was first spotted about 1.20pm yesterday off Shark Island in the eastern harbour near Rose Bay.

It is believed the whale's tail became stuck in a rope.

Rescuers had to abandon rescue efforts last night due to failing light. They were unable to detach a rope that's been wrapped around this juvenile humpback whale.

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Orange buoys were attached to the netting in an effort to slow the whale down and cut it free.

Rescuers also put a GPS tracker on the whale but it become dislodged after just one hour.

The wildlife rehabilitation group ORRCA says it does not believe this is one of the three whales being tracked earlier in the week.

It also reminded people on the harbour to maintain the legal approach distance of 300m to whales.

"Members of the public are reminded to not approach or enter the water near an entangled whale, or attempt to disentangle it."

Any sightings can be reported to ORRCA's 24-hour rescue hotline (02) 9415 3333.