How do you catch a killer in Oz?
Unforgiving – that’s the word to use when describing the Southern Ocean around Bremer Canyon, about 70km offshore of Bremer Bay, in Western Australia’s south. And yet, researchers and tourists alike flock to the broiling sea every year between January and April, intent on spotting orcas in all their raw and wild beauty.
Marine biologist Pia Markovic is one of them. “The area is unique,” she says, “due to the three ocean currents that combine here, and the ocean floor’s topography, where canyon systems and the continental shelf intersect. This creates vertical and horizontal mixing through the waters column, and with hydrocarbons, such as methane, seeping out from the seafloor there is a double influx of nutrients! This creates a highly productive and unique ecosystem, of which killer whales swim at the top!”
“Alongside us [researchers], our passengers collect observational data. That is, we show up and record what the killer whales do. The data includes photo identification, behavioural and social data, and short- and long-term information. We also monitor the health of the animals as well as any potential impact we as a tourism vessel may be having on them. All while providing education and helping inspire our passengers.”
The orcas were first ‘discovered’ off Bremer Bay in the early 2000s by Dave Riggs, a WA filmmaker. He was on an annual tuna research expedition from Esperance to Albany looking for wildlife when he spotted the elongated dorsal fin! In 2013 he produced a film called The Search for the Ocean’s Super Predator, and not too long after that Naturaliste Charters, working alongside Dave, became ran first dedicated expedition to see orcas in Australian waters.
Orca vs blue whale
Recently, Pia has co-authored a paper that describes ‘The first three records of killer whales (Orcinus orca) killing and eating blue whales (Balaenoptera musculus)’, which has international significance. “I was present for two of the three predation events and it is safe to say that as a scientist, my brain was working overtime to try to diagnose what was occurring! Orcas are very fast and if you blink you can miss it. Having multiple camera on the action and an experienced team working together allowed us to capture these world-first events. I have no doubt there will be more scientific papers coming out of the quiet seaside town that is Bremer Bay in the coming years.”
As well, guests aboard a Naturaliste Charter vessel can hope to see pelagic birds, turtles, rays and the weirdly wonderful sunfish. And every time a guest pays their fare to step aboard, they’re helping fund scientific research. “They get to witness the animals and have an incredible day out while the crew collect data and provide education,” Pia says.
Humpbacks of Hervey Bay
Meanwhile, in the waters off Hervey Bay, Queensland, whales of a different kind are also being studied between July and November under the watchful eye of the Pacific Whale Foundation (PWF).
“When the area was recognised as being a potentially important area for whales in the mid eighties, researchers from PWF arrived and started studying the whales in this unique area,” says Andrew Ellis, Director Australian Operations. “PWF had been studying whales in Hawaiian waters since 1980 and jumped at the chance to compare the different populations. This was the start of the longest-running research programme on a population of whales in the Southern Hemisphere that continues today.
“Long-term monitoring allows for population trends to be assessed and can help identify any patterns. The backbone of these studies is our photo-identification (photo-ID) programme. This allows for population estimates to be generated and gives a baseline from which to assess trends and identify potential impacts of human activity.
“As PWF has grown and evolved, so too has its mission. The long-term goal of our research programme is to identify and assess major threats to whales and dolphins around the world and develop science-based solutions to mitigate these problems.”
In 2012, to financially support the expansion of the research programme, PWF Eco-Adventures Australia was established and offers commercial whale watching eco-tours out of Hervey Bay. According to Andrew, all profits continue and expand the work of PWF.
This work includes research into whale numbers, behaviour, climate impacts and more, such as the finding recently that commercial swim-with-whale tours was having a detrimental effect on the whales in Hervey Bay.
“The results from our three-year study found that whales changed their behaviour and significantly reduced the amount of time spent resting when people were in the water with them compared to their behaviour in the absence of swimmers,” Andrew says. “We also compared the impacts of swim-with-whale tours to more traditional boat-based whale-watch tours, and again found that the swim-with-whale tours significantly impacted the whales’ behaviour when compared to whale watch tours.”
At Hervey Bay, in addition to continuing its photo-identification programme, PWF has commenced a new research study looking at the body condition of the whales in the bay. This research uses a technique known as aerial photogrammetry to assess how healthy an individual is based on its size – a healthy whale is usually a big whale.
In Hawaii, PWF also has a long-running study on the ecology of humpback whales, dating back to the early 1980s. Hawaii differs from Hervey Bay as it is a breeding ground, whereas Hervey Bay is an important resting point on the southern migration route. Collecting data from these two different areas allows PWF to compare and contrast the numbers, behaviour and health of the animals.
“While they are not the same breeding stock, it does allow us a degree of comparison of two different important locations,” Andrew says. “We also conduct research on humpback whales in Ecuador where we collect similar data to Hervey Bay and Hawaii to learn about the ecology of the whales there and assess the impacts of human activity, particularly bycatch and entanglement. Recently, we have also expanded our reach around the Pacific by implementing a new study on the swim-with-whale tourism industry in Japan and we provide financial support for a blue whale study in Chile. We hope to continue these relationships and expand our conservation impact in the future.”
Cleaning up our act
During each year, in conjunction with local volunteers, PWF runs beach clean ups in the Hervey Bay area. In previous years, this debris was disposed of, or recycled by the local council, all with the aim of preventing this debris from entering our ocean. Nowadays PWF looks to go further by collecting data on the type and quantity of debris collected. These data are entered into the Australian Marine Debris Database managed by Tangaroa Blue in order to monitor and track the types and origins of debris found.
“This is used to better inform legislators about future changes needed in managing this worldwide problem. Clean up days from all around the Australian coastline enter their own data which is collated on both a local and federal perspective. PWF operates a similar programme in Hawaii and supports initiatives that enhance traditional beach clean-ups from simply removing debris to studying this problem and tackling it at the source.”
How can guests help?
While guests are marvelling at the majesty of Humpbacks in the bay, PWF researchers are hard at work collecting as much information as possible.
“Collecting data from Ocean Defender is different to when our researchers are on their own vessel,” Andrew says. “The commercial whale-watching trip is very much tailored to giving the guests the best possible tour while respecting the regulations surrounding whale watching. However, that doesn’t mean that we can’t also contribute to the research.
“On board Ocean Defender, our captain and crew record their sightings using our ‘Whale and Dolphin Tracker’ app, which is freely available to the public, and these sightings can be viewed for free on our website.
“Data from our app supplement dedicated research surveys; for example, we contributed dolphin sightings from Ocean Defender to be considered in the new marine park zoning plan. We also encourage our passengers to support our photo-ID research by submitting their fluke photos to our research team here.
“Additionally, we used our commercial vessel as an opportunistic platform to assess the impacts of whale watch tours and swim-with-whale tours on humpback whales.
“This year in Hervey Bay we are excited to begin a new study on the dolphin species in the bay. We aim to assess the population sizes of the three resident species of dolphin; the Australian humpback dolphin, common bottlenose dolphin and the Indo-Pacific bottlenose dolphin. This is an important study, as the Australian humpback dolphin is listed as vulnerable by the IUCN and the local government. The information regarding these species along the Queensland coast is patchy and only small-scale studies in a few areas have been carried out. This research will help build a clearer picture of the dolphin populations in Queensland and will be used to assess potential impacts for management purposes.”