Crucial humpback whale mating grounds discovered off Australian coast


Griffith University researchers examine humpback whale habitat Photo by Todd Cravens on Unsplash

Researchers have discovered two key locations on Australia’s East Coast that are important humpback whale nursing, socialising and mating grounds.

Griffith University marine biologist Dr Olaf Meynecke said he studied the movements of 5400 humpback whales in Hervey and Gold Coast Bays between 1999 and 2018 and found the areas were “critical” to the species.

“This is the first study to look at the behaviour of humpback whales in two different regions to determine how they use the areas,” Dr Meynecke said.

“It showed that the whales used the two bays for many similar activities, such as resting and socalising, but that there were distinct differences.

Dr Meynecke says the researchers found more competitive group of humpbacks that displayed aggressive behaviours in the Gold Coast Bay, whereas Hervey Bay was predominantly a resting area for mother-calf pairs.

“Overall, our results suggest that the Gold Coast Bay provides habitat for a wide range of critical humpback whale activities, in particular for resting mother-calf pairs, mature whales seeking copulation and socialising immature whales,” Dr Meynecke says.

“Hervey Bay had a higher number of mother-calf pair sightings, confirming the areas an important resting site.”

The movements and migratory behaviour of these oceanic giants largely remains a mystery and experts say this type of study is important in aiding conservation and oceanic management.

Griffith University environmental scientist Professor Brendan Mackey says the research will help officials to properly manage the eco-tourist industry, such as whale watching and understand how it affects the whales’ migrations and behaviours.

Not-for-profit whale conservation organisations Humpbacks and Highrises and The Ocean Project were involved in the collection of the data from whale-watching boats.

Humpback whale mothers are easily disturbed by boats, which can result in increased dive times, changing path and decreased respiratory rates, which can affect the animal’s limited energy reserves, according to the scientists. Dr Meynecke says the study shows that Hervey and Gold Coast Bays are critical habitats during Humpback migration and should be considered whale protection areas.

When commercial whaling of humpback whales was ceased in 1963, their numbers between 1000 and 1500, and the species teetered on the brink of extinction.

Since then, numbers have steadily risen 10-15 per year and Dr Meynecke says that ongoing studies of whale’s habitats and behaviours are much needed to maintain healthy populations.