An ancient nursery reclaimed
Each year between May and October, the waters of the Great Australian Bight Marine Park are a nursery for the southern right whale (Eubalaena australis). After feeding for the summer in sub-Antarctic waters, these endangered animals migrate thousands of kilometers to the sheltered bays of the Bight to give birth and nurse their young. The area around the Head of Bight is a primary calving ground, where scientists have observed as many as 70 mother-and-calf pairs at one time. At the peak of the season, over a hundred individuals can be seen from the cliff-top viewing platforms.
This annual return shows the species' recovery. In the 19th century, whalers hunted this species, which was considered the "right" whale to hunt due to its slow speed and tendency to float after death, to the brink of extinction. By the time the industry collapsed around 1845, some populations had been reduced by 75%. The whales are now protected, and their slow recovery is monitored by scientists who identify individual animals by the unique patterns of hardened skin, called callosities, on their heads. The return of these whales to the same ancestral bays indicates cultural memory, a knowledge of safe havens passed down through generations, that persisted even when their numbers were critically low.
Where the desert meets the deep sea
The marine park protects the whales and other species. It covers a vast area of 45,822 square kilometers, with depths ranging from 15 meters to over 6,000 meters. The park's northern boundary is defined by the Bunda Cliffs, a limestone escarpment that stretches for over 200 kilometers and reaches heights of 120 meters. These cliffs are considered the longest continuous line of sea cliffs in the world and were formed when Australia separated from Antarctica around 65 million years ago.
Below the surface, the park's biodiversity is high. Approximately 85% of the known marine species in this region are endemic, meaning they are found nowhere else on Earth. The seafloor contains the world's largest known temperate carbonate platform and globally unique ecosystems of sponges, sea squirts, and aquatic invertebrates called bryozoans. Deep-sea canyons cut through the continental shelf, some containing giant holes up to five kilometers wide. This entire ecosystem is fueled by a massive seasonal upwelling of cold, nutrient-rich water that supports everything from microscopic plankton to the endangered Australian sea lion (Neophoca cinerea), about 80% of whose population is found here.