Bizarre markings spotted on whale swimming at Port Macquarie NSW spark confusion among experts about what caused them

A whale with unusual markings spotted off the Australian coast has experts intrigued about what caused it.

The humpback whale was spotted off Port Macquarie, on the NSW north coast, on Saturday by marine mammal and wildlife photographer Jodie Lowe.

The stunning footage captured by Ms Lowe shows white spots crisscrossing the whale’s body as it breaches the ocean’s surface.

Mrs. Lowe told it Yahoo News she saw the humpback swimming with three other whales and believed the whale was a juvenile and appeared healthy.

There are several theories about what could have caused the bizarre markings.

They range from a skin condition, a lightning strike, fishing nets, cables, ship propellers or even as a result of an encounter with another whale or even a jellyfish.

The unusual markings on the humpback whale have experts intrigued about what causes them

Whale expert Dr Rob Harcourt described the markings as ‘amazing’.

“Very intense scarring like this can result from entanglement in fishing nets – although these are usually more linear and evenly distributed,” the emeritus professor of marine ecology at Macquarie University told the outlet.

‘They can also arise from intraspecific fights between males; the barnacles on the skin can cause many scratches on the relatively vulnerable, smooth skin.’

Port Macquarie is known as an ideal whale watching destination.

About 40,000 humpback whales make the world’s longest mammal migration between May and November each year.

The whales travel more than 5,000 km from feeding grounds in Antarctica to the subtropical waters of Queensland, where they breed.

The route is known as ‘Humpback Highway’.

The whales then return to Antarctica in the spring with their calves on foot.

Humpback whales are known as the stars of the whale season when they breach the surface in a spectacular acrobatic display.