Close to a five-hour drive from Perth / Boorloo and settled between Albany / Kinjarling and Esperance / Kepa Kurl lies Bremer Bay, a hidden gem on Western Australia’s south coast. With only 400 permanent residents, the small outcrop boasts pristine beaches, bountiful fishing locations, and breathtaking coastal views. The town itself is set upon the main beach and acts as the perfect starting point for a variety of ecotourism and outdoor activities, including snorkelling, surfing, and diving.

In close proximity to Bremer Bay lies the Fitzgerald River National Park which is rich in wildlife and plant life, with more native species of flora than the whole of the UK. The National Park was internationally recognised by UNESCO as a unique biosphere, joining Uluru and Kosciuszko as one of only 14 similar areas in Australia. On various walking trails, visitors can marvel at abundant birdlife, reptiles, marsupials, Australian staples such as kangaroos and emus, various plants, including the hakea, one of the park’s most prominent species, as well as tremendous views of the coastal plain from the top of West Mount Barren. One of the main highlights here is the annual wildflower season as Western Australia is home to the largest collection of wildflowers on earth.

Though the natural wonders on the coastline attract visitors throughout the year, most flock to the area to head offshore instead as a wide range of marine wildlife uses the Bremer Bay region, including long-finned pilot whales, false killer whales, common dolphins, Oceanic bottlenose dolphins, blue whales, sperm whales, mola mola, long nosed fur seals, Australian sea lions, various seabirds such as the wandering albatross, and, on rare occasions, baleen whales such as Bryde’s whales and minke whales. Between July and October, migrating Southern right whales can also be spotted off the coast, while leafy seadragons hide and breed amidst seagrass meadows closer to shore.

The real stars of the region, however, are large pods of orcas that annually hunt off Bremer Canyon between January and April. Bremer Canyon, a relatively narrow submarine canyon, lies just 70km off the coast, at the edge of the continental shelf, and leads to the abyssal plain of the Southern Ocean. It lies amidst the Bremer Marine Park, a 4,472 km² Marine Protected Area, with a depth range of about 15 to 5,000m. Thanks to its unique and deep underwater topography, the canyon’s complex currents and nutrient-rich waters provide a fertile ground for research. Already known as a biodiversity hotspot for marine megafauna, a recent expedition, led by researchers from the University of Western Australia with the help of the Schmidt Ocean Institute, discovered diverse ecosystems inhabiting the cold waters deep within the canyon.

The research team collected deep-sea corals, associated fauna, seawater, and geological samples from the abyssal depths to the continental shelf with the help of a deep-sea remotely operated vehicle, aptly named SuBastian. “We have already made a number of remarkable discoveries from the Bremer Canyon,” said Dr Julie Trotter, the chief scientist from UWA who led the expedition. “The vertical cliffs and ridges support a stunning array of deep-sea corals that often host a range of organisms and form numerous mini ecosystems,” she added. Such rare records of these deep-sea habitats are a new and very important contribution to the Marine Parks, which will help managers as well as the broader community to better understand and protect these previously unknown ecosystems.

Thanks to the special underwater topography of Bremer Canyon, cold, nutrient-rich water flows in from the Southern Ocean and upwells along the edges of the continent’s shelf, attracting large groups of orcas between January and mid-April. The upwelling of nutrient-rich water creates a marine environment supporting an extraordinarily high biomass and attracting an abundant array of sea life, feeding on the plentiful food sources present at this time of year. In 2005, a Spanish research vessel first reported large numbers of orcas in the region. Numerous sightings have been made since, resulting in the region’s reputation as the southern hemisphere’s largest orca congregation, and Australia’s only location where visitors are guaranteed to spot these animals during Australian summer.

Jade Cantrall, marine biologist working at Naturaliste Charters, one of the whale watching companies operating out of Bremer Bay, explains: “The Bremer Bay sub-basin is a unique and biodiverse system that incorporates a chemical process and natural breakdown of methane hydrates that seep from the ocean floor, fuelling the complex system.” Cold upwelling currents bring these nutrients into the first 200 metres of surface water, the photic zone, where photosynthetic phytoplankton can utilise these nutrients to photosynthesise.

“Working up the food chain, zooplankton, fish, squid, and larger species such as the orcas all flock to the area as it is essentially a smorgasbord of food available throughout the varying topography of canyon systems below,” adds Cantrall.

As the first company to offer whale watching tours in Western Australia’s south west, Naturaliste Charters has been in the business for over 30 years. In 2009, current owners Paul and Alison Cross took over the business to continue the tradition of responsible whale watching in Bremer Bay. “Since then, various research projects, unique on-board learning experiences, and the establishment of new oceanic expeditions such as the Bremer Bay Orca Expeditions have been developed,” explains Cantrall and adds: “Paul and Alison are committed to enriching lives by building connections between guests and the extraordinary marine biodiversity of the south-west region. Their unique approach intertwines conservation, research, and tourism.” The company’s special ecotourism approach educates people about the orcas and their role in the environment. “Educating passengers on the human impacts that these orca face, whether they’re inshore or offshore populations globally is vital in helping people understand what role they can take to assist in creating less damage,” says Cantrall.

While orca populations from different regions have varying levels of success, potential threats to the orcas generally include human impacts such as reckless recreational and commercial vessel activities, discarded fishing gear, water pollution, noise pollution, overfishing and warming seas that can affect those orca populations that use ice sheets for their feeding techniques. About the Bremer Canyon population, Cantrall says: “It is hard to determine with our little time observing this population the specific impacts that may affect these orcas residing off Bremer Bay.” She estimates that around 300 healthy individuals utilise the area and at least one new calf is spotted every season. “This is a promising sign to the health of this population,” she adds.

To find out more about the Bremer Bay orcas, marine biologists on board the Naturaliste Charter boats take ID photographs of the orcas to note which individuals from each population the tour operators were interacting with. “We also create a marine log detailing observational based data upon the animals encountered which aids in future understanding of the bigger picture of the Bremer Bay system collectively,” says Cantrall.

At this stage, researchers are unsure whether this specific orca population is primarily using the Bremer Canyon system for the Australian summer and autumn months and then moves elsewhere or if all or some parts of that population are actually localised to the southwest of Australia permanently, and use different regions of the coastline to their advantage and feed on specific food sources available during different times of the year. Cantrall argues that, as an example, the orcas could potentially come closer to the coastline when the Southern right whales move up from Antarctica after summer to feed in the shallows of southern Australia in late April and early May during their winter calving and breeding season.

“The orcas could be altering their diet to feed on the Southern right calves that are born as opposed to the variety of beaked whale species, fish and squid that they feed on within the sub-basin off the continental shelf during Australian summer and autumn months,” she explains.

Every orca season, the biologists win invaluable insight into the movements of these orcas and hope that some of their secrets can soon be revealed. Until then, the tours will continue to observe the populations and educate the public about these magnificent animals. When asked about her most special orca encounter, Cantrall explains: “One day, we saw three juveniles who were super interactive. They were within arm’s reach, looking like they were almost kissing the GoPro we had in the water. They were so inquisitive.” She adds: “They would then swim off and do a lap around the side of the vessel and come back to the back of the boat for more close-up shots and playing with each other whilst looking at the GoPro. They did this for about 45 minutes at least. When we thought it couldn’t get any better, the afternoon brought about an incredible predation event.” She continues: “We watched a group of 30 to 40 orcas passively herd this poor beaked whale at the surface. After about 20 minutes of build-up, we watched them tear apart this whale and then share the meat between individuals. It was absolutely mind blowing. The fact that we had all this action in one day was crazy and to witness the change in behaviour from friendly and cute playfulness off the back off the boat to then seeing them feed in that manner was humbling to say the least. I was completely in awe.”

To protect such special interactions for generations to come, an independent review urged in 2016 that Bremer Bay canyon should be protected from extractive mining activities by expanding the marine national park zone to cover 70.93 per cent of the Bremer commonwealth marine reserve, including the Bremer Bay canyon. An expansion would see the area covered increase by 3,000 square kilometres. In more recent news, in early 2024, the Western Australian government revealed its plans to close a quarter of waters between Bremer Bay and the South Australian border to all fishing activities as part of its new South Coast Marine Park plan which would span 1,000 kilometres of coastline. Reece Whitby, minister for environment, told ABC News: “I’m very optimistic about this, I think this will be a Marine Park that will rival Ningaloo and the Great Barrier Reef.” The draft marine park is currently open for public comment and final decisions can be expected later in 2024.