Humpback whales make surprise shift to calve in Gold Coast

Murdoch University, Jeremy Wolfe

Nicolas RAKOTOPARE

Researchers have found humpback whales calving 1000km south of their usual nursing grounds. Picture by: Humpbacks and Highrises https://www.humpbacksandhighrises.org/

Whale experts are warning that changes in migrating humpback whale calving behaviour is putting their newborns at risk after the ocean giants were discovered giving birth more than 1000km south of their regular calving grounds.

Griffith University marine scientist and Humpbacks and High-Rises CEO Dr Olaf Meynecke is calling for better protection and slow-go areas in the Gold Coast Bay after he recorded 74 calves in the area between 2013 and 2016.

Before now, the east Australian humpback whale’s main calving area was the Great Barrier Reef – hundreds of kilometres up the coast.

“The area definitely is being used by newborns and that means that the females are likely to give birth in the Gold Coast Bay or even south of the Gold Coast Bay, we’re probably going to see more of those mother calf pairs and those newborns in the area,” Dr Meynecke says.

It is not known why the cows are birthing so far down the coast but Dr Meyneckes said rising numbers in population, changes in food supplies and shortened migration patterns to conserve energy are possible reasons for the move.

A humpback and her calf in the Gold Coast Bay. Picture credit: Humpbacks and Highrises

He warns that these are only theories and that the causes of the shift are still in the research stages.

Although the warm shallow waters off the Gold Coast Bay provide suitable calving habitat for the whales, threats, such as boating, noise pollution and entanglement risks, pose a hazard for newborns.

“The area isn’t a protected area like the Great Barrier Reef where the original calving grounds are, so that means there is definitely less protection,” Dr Meynecke says.

He says people need to be more aware about the rules of interacting with whales to better protect mothers and their calves.

Dr Meynecke wants birthing and whale resting areas to be officially recognised and marine speed limits enforced to protect the large mammals and their bubs.

“I think that will also make it safer for people because the animals are resting on the surface a lot,” Dr Meynecke says.

He would also like to see shark nets replaced during the whale season to reduce the risk of entanglement.