Cetaceans are some of the most iconic animals on the planet, yet few of the 45 species of whales, dolphins and porpoises known to occur in Australian waters have been extensively studied to date. Historical commercial whaling records and recent modelling studies suggest that the submarine canyons within and around the Bremer Marine Park provide favourable habitats for a number of cetaceans, including sperm, beaked, and killer whales. The latter have been reported to concentrate in unprecedented numbers in the Bremer Sub-Basin over the austral summer months, forming what is likely the largest seasonal aggregation of the species in the Southern Hemisphere. However, little data on the animals’ ecology, population abundance, or movements currently exist, and while the majority of killer whale encounters have occurred around the heads of the Knob and Henry Canyons to date, it remains unclear whether this area represents a discrete and unique hotspot or whether the Bremer Marine Park may support additional aggregations.
Under the NESP Emerging Priorities scheme, the Minister for the Environment and Energy, the Honourable Josh Frydenberg MP, accordingly committed research funds to the Marine Biodiversity Hub (MBH) to assess the extent and likely drivers of the Bremer megafauna hotspot, which is currently fuelling a rapidly growing tourism industry. As part of the programme, aerial surveys were implemented to assess the presence, numbers, behaviour and distribution of large air-breathing vertebrates throughout the region. The resulting data provide a critical baseline for understanding when and how cetaceans and other charismatic predators use the Bremer Marine Park. Such knowledge is key to helping managers and policy-makers meet national legislative requirements regarding the adequate conservation of Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) listed species