Unexpected humpback whale sighting sets off shark alarm at Sydney beach

Residents in Sydney's Northern Beaches woke to a surprise visitor this morning, with a juvenile humpback whale swimming off Little Manly Cove.

The unique sighting of the younger marine mammal comes ahead of the peak migration season.

The sight left witnesses gobsmacked.

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"I've never seen a whale come this close or up that close, it was truly something special," Alex Smith told 9News.

Locals treated to the unique sighting after the adolescent male likely took a wrong turn on his early journey north to migrate and mate.

"Maybe it got chased in here by an orca, maybe it was chasing a feed or it simply just wanted to come and explore our great harbour," Steve Trikoulis from Orrca told 9News.

The whale had several obstacles to avoid as he searched for a way out, including line from anchors of boats moored in the area, as well as swimmers and kayakers.

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The young marine mammal safely made its way outside the heads into the open ocean, leaving behind a very timely message for migration season.

"When you do see a whale out in the wild maintain at least 100 metres away from it," Trikoulis said.

"If you do see a calf with it, extend that distance to 300 metres."

Getting back on track wasn't all smooth sailing for the young humpback as he set off the shark alarm passing by North Curl Curl.

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