Tracking the giants of the deep in the annual southern right whale survey off Australia's south coast

Updated

Covering thousands of kilometres in a light plane, an aerial survey is documenting the remarkable recovery of the southern right whale.

Photographer Andrew Halsall hangs out of the window of a small four-seater plane skimming 400 metres above the Great Australian Bight.

"Just there, beyond the wing tip," he calls out to pilot Jenny Schmidt, who descends to just above the coastline, tipping the plane 90 degrees onto its side until the horizon is vertical.

She turns the Cessna 172 in a tight circle, orbiting their target — a southern right whale and its calf.

Each winter, the whales journey north from Antarctica to the southern Australian coastline in search of the warmer waters that form their breeding ground.

A long history of whaling left the right whale virtually extinct in Australian waters for the first half of the 20th century. But increased sightings near Albany on Western Australia's south coast in the 1970s led biologist John Bannister to begin an aerial survey in 1976 to observe their recovery.

Now, each year Ms Schmidt and Mr Halsall embark on an adventure from Fremantle in WA to Ceduna in SA to record their numbers for the WA Museum.

Leader of the Australian Marine Mammal Centre at the Australian Antarctic Division, Mike Double, says when the survey first began, the total count of whales was sometimes less than 10.

"What we're really interested in is mums and calves," he says.

"By the mid-1990s you're seeing about 90 mums and calves, and now you're seeing about 300 or 400 across the aerial survey."

The survey lives on as a legacy of Mr Bannister, who was the director of the WA Museum for 17 years and died in August last year.

"John was an amazing character. He was a giant of whale science and research," Dr Double reflects.

"A tall imposing man with a proper English accent and an incredible passion for marine mammals, and whales in particular."

Australia at its most extreme

Along the Great Australian Bight, a rugged coastline stretches as far as the eye can see.

The terrain compacts red, brown and white rock, which is then washed white by wild waves.

The flat landscape abruptly ends at a sheer cliff face framed by a white border of breaking waves, before the azure sea takes over as far as the horizon.

Between Caiguna in WA and Ceduna in SA, Ms Schmidt and Mr Halsall count 101 adult southern right whales, 77 calves and one humpback whale.

On another day their observations include a very big shark and a large leatherback sea turtle.

Dr Double says there were about 10,000 southern right whales in Australia before whaling dramatically reduced their numbers.

The right whale got its name because it was the "right" whale to hunt.

"They're the right whale because they're incredibly oil-rich, they have very thick blubber and they come very close to shore," he explains.

"The other thing is they float when they're dead. Not all of the large baleen whales float, so they were easier to take back to shore-based whaling stations."

A slow but steady recovery

On day four, the survey team land on a small gravel runway to meet with Great Australian Bight Right Whale Study research scientist Rhianne Ward at Nullarbor Roadhouse.

She is preparing for a day of counting along the cliffs at Head of the Bight.

Ms Ward says while numbers are slowly increasing, there is still a long way to go.

"In Australia, the most recent estimate is 3,500 individuals," she says.

"That includes 3,200 in the south-west, where the aerial survey runs, and it's estimated there are roughly 300 individuals in the south-east."

Ms Ward says about 2–5 per cent of the population of southern right whales are born white, but sightings of adult white whales are fairly rare.

Greater exposure to anthropogenic threats such as vessel traffic and development in the south-east could account for the whales' lower recovery rate the further you head east.

Dr Double says another factor could be that the whales were hunted more severely in the south-east, where they were more accessible.

"The populations in south Western Australia and Head of the Bight have shown greater recovery because there were simply more animals that survived," he says.

A fingerprint for a whale

As Ms Schmidt circles above the whale and its calf, a scribe notes numbers and locations, while Mr Halsall aims to get a clear image of the whales' heads, capturing their unique callosity patterns.

Ms Ward says each pattern is unique, like a fingerprint.

"By viewing an animal's headshot, we are able to ascertain if we've seen it previously and we can work out its life history information — how old it is, how often it calves," she says.

In the space of a few moments, Mr Halsall snaps hundreds of photos. He and Ms Schmidt have conducted the surveys together since 1997.

"When we first began we were shooting film, and instead of a GPS we were using a 30-page A3 map," he remembers.

"I remember being so motion sick, but you know, you'd throw up in a bag and then you'd have to keep shooting photos."

"I remember you laying there on the ground in Esperance, not wanting to get back in," Ms Schmidt says.

They break for a stopover at the Caiguna Roadhouse, where she sits down next to two lonely public phone booths to check the local weather forecast and confirm the final flight plan.

They are the same booths she relied upon 20 years ago to gather this information from Airservices Australia, but advances in technology mean she can now do the same on an iPad.

Ms Schmidt says the team needs six days of good weather to conduct the survey, so often she follows a winter front to Ceduna, flying in the good weather that results.

"On the way back, it's not so easy. Sometimes we get stuck," she admits.

Pilot and photographer working as one

This year they luck out in Caiguna, which had a population of eight people at the 2016 census.

They take the chance to stretch their legs after six days beside each other in the aeroplane.

The pair say teamwork is a crucial part of the survey.

"Jenny needs to think like a photographer in setting the plane up to position it right, and as you spiral around the whale the reflections of the sunlight off the water make it difficult," Mr Halsall says.

Ms Schmidt says Mr Halsall's in-flight coffee-making skills are the most important thing to her, next to aircraft fuel.

The duo took over the survey from John Bell, who piloted every flight from 1976 to 1995 before dying in an aircraft accident at Albany in 1996.

Mr Bell lived through an interesting transition, going from a pilot who helped hunt whales for the Cheyne Beach Whaling Station to becoming the first to fly the aerial survey aimed at conserving their numbers.

'An amazing spectacle'

This year, the team counted about 560 southern right whales along the southern Australian coastline.

Last year, there were close to 800, but Dr Double and Ms Ward say these lower numbers are fairly normal due to the right whales' three-to-four-year breeding cycle.

The southern right whale is recovering at an approximate rate of 6 per cent each year.

Dr Double says it is unknown if the southern right whale population will every truly recover to pre-whaling numbers, but he expects the population to continue to increase for the foreseeable future.

He says there are things the general public can do to help.

"Respect the animals — it's in your interest to do that, they can be aggressive," he warns.

"We're in the age of the selfie and people like to go up to these whales in their kayaks and jet skis. I don't think people realise the animal can be quite upset by loud noises around it."

He wants people to be respectful of national guidelines around distances that should be kept from a whale.

"These are magnificent animals, and I'd encourage people to go and see them in places like the Head of the Bight where you can watch from the shore and a cliff top — it's an amazing spectacle."

Credits

Reporting: Molly Schmidt

Molly Schmidt Photography: Molly Schmidt and Andrew Halsall

Molly Schmidt and Andrew Halsall Production: Liam Phillips

*The reporter Molly Schmidt is the daughter of pilot Jenny Schmidt

Topics: mammals---whales, whaling, animal-science, conservation, wa, sa, perth-6000

First posted