Minke Mysteries: The Great Barrier Reef’s most elusive whale

Original story published in Tropical North

Until 1981, dwarf minke whales, animals that can weigh six tonnes and grow up to eight metres in length, were yet to be discovered. It was only the precise drawings and field notes shared by Rob Prettejohn after encountering a mystery whale on the Great Barrier Reef that led to the astonishing discovery. 40 years of scientific study later, a myriad of questions surrounding these elusive creatures remain unanswered. 

Tropical North Queensland is the only place in the world where people can interact with dwarf minke whales in the water. For just a few weeks each year, a handful of tourism operators open their liveaboards to this exclusive natural encounter on the Ribbon Reefs to the north of Cairns. Dr Matt Curnock of the Minke Whale Project, a scientific study based at James Cook University, describes the research currently being undertaken to learn more about the biology and behaviour of dwarf minke whales:

“A lot remains unknown about where they feed, where and when their calves are born, what risks and threats they face when outside the relative safety of Australian waters, as well as how their behaviour changes in response to interactions with vessels and divers.”

Image by Jemma Craig

Quite predictable in their migratory behaviour, the whales return to the same general area and even to the same dive sites year after year for just a few months. The small size and colour of the whales make them difficult to spot on the surface of the water as they blend in with sea conditions. Therefore, most interactions usually begin on their terms. They are curious creatures, possibly attracted by the low frequency hum of the engines, so are often seen popping up right next to vessels. However, Curnock describes that this playfulness becomes most apparent underwater.:

“I can recall an encounter with “Pavlova”, a mature female around six and a half metres long, back in 2007. She would swim up very close to people and eyeball them, her tail would sink until she was vertical in the water, and she would then slowly revolve on her long axis, like a pirouette. She was the first whale we’d ever seen do that before, but we’ve seen pirouetting by other whales a number of times since. There’s no other wildlife watching experience quite like it.”

Image by Jemma Craig

It’s remarkable really, that tourists have the opportunity to swim with these rare creatures in the wild, each and every year. Fortunately for researchers, the tourism operators actually allow them much more frequent access to study the whales than would ever be possible with a private research vessel. The Minke Whale Project simply wouldn’t exist without the support from the tourism industry. 

Not only have researchers been welcomed onto tourism vessels since the mid 1990s, but tourists themselves have actually played a large part in contributing to the scientific study. Under an approach commonly known as citizen science, researchers encourage tourists to submit their underwater photos of the whales for identification. Although they are the second smallest baleen whale in existence, dwarf minke whales have the most complex colour pattern – which makes it possible for scientists to distinguish them from one another and study the movements and behaviours of individual whales.

Image by Matt Curnock

Other species of minke whale are studied in numerous places around the world, including Antarctica, and those researchers have produced some very exciting results about feeding and spatial ecology. A key difference for studying the Great Barrier Reef population of dwarf minkes is that researchers encounter them during their breeding (rather than feeding) season. Their behaviour is quite different and there’s a lot that remains unknown about their use of the reef habitat during this important life history phase. As such, collecting new behavioural data each year is one of the key focuses of the project. 

Curnock remarks,

“From year-to-year members of the team and postgrad students use different equipment or collect different sorts of data – for example satellite tracking, acoustics, and photogrammetry. A few years ago, using satellite tags, we learned about their migration path from when they leave the Great Barrier Reef and head south to the Southern Ocean, but a lot remains unknown.”

Image by Matt Curnock

The biggest mystery of all, though, remains with the basic taxonomy of the whales. Although they’re currently regarded as a subspecies of the northern hemisphere minke whale, there have been questions raised about their distinctiveness, and as such, their taxonomy is still unresolved. Several students have been working on their genetics for a number of years now, and are hopeful of resolving this issue at some point in the near future.

For a subspecies of whale with over 25 years of history interacting with tourists and researchers on the Great Barrier Reef, it seems remarkable that so many mysteries still surround the dwarf minke. With limited public funding available for projects such as the Minke Whale Project, research teams heavily rely on the support of tourism operators and travellers to continue to learn more about the ocean’s fragile ecosystems and the marine species that inhabit them. 

Find out more at Minke Whale Project

Images by Jemma Craig (Tourism & Events Queensland) & Matt Curnock