Humpbacks are an Australian success story. They have two advantages most whales don't

The Age

2 days ago

It is peak hour on the humpback highway off the east coast of Australia, a sign of one of the greatest conservation successes of the 20th century, but half of the world's great whale species are yet to recover from commercial whaling.
During the 20th century, nearly 3 million whales were commercially harvested, driving many species to the brink of extinction. Some species have rebounded – humpback numbers on the east coast of Australia have grown from less than 100 in the 1960s to about 40,000 now.
Yet many other species such as blue whales are not doing nearly as well. Of about 15 species of great whale, the International Union for Conservation of Nature lists two as critically endangered, three as endangered, two as vulnerable and one as near threatened.
Dr Olaf Meynecke, a research fellow at the Coastal and Marine Research Centre at Griffith University, said humpback whales have two advantages.
'Humpback whales can have a calf every year if the conditions are very good, but at least every two years,' Meynecke said. 'And humpback whales can switch between different prey – different fish species or krill. They also develop advanced social feeding strategies, sharing food amongst each other and information about it.'
By contrast, Meynecke said, blue whales need to feed on krill most of the time to survive, and can only give birth every two to three years at maximum.
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Research last year from the Australian Antarctic Division suggested that blue whale populations may be starting to recover.
The World Wide Fund for Nature on Wednesday released Blue Corridors, an interactive mapping tool to show the migratory routes and range of different species.
The collaboration between WWF and more than 50 global research groups combines over 3.2 million kilometres of satellite tracking data from more than 1400 migratory whales, with information on overlapping threats and conservation solutions.
Chris Johnson, the global lead of the WWF Protecting Whales & Dolphins Initiative, said the animation collates all the data and plots it over a year to show how the whales move in both space and time. The map is launching with eight whale species, but there are plans to expand.
Johnson said this would help the Australian government update its 'biologically important areas' – critical ocean areas that are key for various species – to inform how to reduce risks such as ship traffic or noise from the seismic surveys or construction of offshore oil, gas or wind projects.
'The aim is to make this transparent and open,' Johnson said. 'Right now when there's oil and gas exploration, the data is actually owned by the company doing the environmental impact statement, and you can only find very limited data online from seismic surveys, for example.'
Minke whales and 'underwater microphones'
In a separate development, while on his industry placement at Accenture, University of Sydney student Oscar Mower, 22, developed AI technology that can recognise the song of the minke whale.
'There are millions and millions of 'hydrophones', which are underwater microphones, and they're scattered around coastlines all around the world,' Mower said. 'They pick up the very diverse ocean soundscape, and essentially what this model does is it analyses these soundscapes and identifies minke whale vocalisations.'
Mower said there was a lot of research on bigger whales, while not much was known about the migratory patterns of minke whales, but his techniques could be broadened out and applied to other species as well.
Antarctic minke whales are listed by IUCN as near threatened. Johnson said there was scientific debate about whether they were a separate species to common minke whales, found in the northern Pacific.