Did you know: The Rakali - Australia's Remarkable River Hunter
- Nhanta
- 13 minutes ago
- 5 min read
Meet the native semiaquatic mammal quietly thriving in Australia's waterways
At first glance, you might mistake it for an otter — sleek, whiskered, and perfectly at home in the water. But the rakali (Hydromys chrysogaster) is something uniquely Australian: a native semiaquatic rodent that has quietly evolved over millions of years to become one of the country's most specialised and ecologically important freshwater predators. Also known as the Australian water rat or, in some regions, the rabe, the rakali is found across waterways from Queensland to Tasmania and as far afield as New Guinea — yet remains surprisingly little known to most Australians.
Understanding the rakali means understanding something important about the health of Australia's rivers, wetlands, and coastal waterways. Where rakali thrive, ecosystems tend to follow.
A Body Built for Water
The rakali is a medium-sized mammal, measuring 23 to 37 centimetres in body length, with a thick, muscular tail adding a further 24 to 35 centimetres. Adults typically weigh between 340 and 1,275 grams, with males generally larger than females — though their tails are roughly the same length in both sexes.
Everything about the rakali's body is designed for aquatic life. Its fur is dense and water-resistant, ranging in colour from dark brown or slate grey on the back to a vivid orange or creamy white on the belly. The hind feet are partially webbed, providing propulsion through the water, while the long, sensitive whiskers — called vibrissae — help detect movement and prey in murky conditions. Perhaps the most distinctive feature is the tail, which ends in a white or golden tip and is used as a rudder when swimming.
Unlike the platypus, which closes its eyes underwater, the rakali keeps its eyes open while diving, allowing it to hunt with precision in rivers, lakes, and estuaries. It is, in every sense, a purpose-built predator of the freshwater world.
Where Rakali Live
Rakali are found across all Australian states and territories, with the notable exception of the arid interior, where permanent water is scarce. They inhabit slow-moving rivers, creeks, lakes, wetlands, estuaries, and coastal bays — anywhere that offers permanent water and low, vegetated banks suitable for burrowing. Their distribution extends to Tasmania, parts of south-western Western Australia, and the island of New Guinea.
One of the rakali's great strengths is its flexibility. It adapts readily to fresh, brackish, or saltwater environments, and has even been spotted in urban farm dams, irrigation channels, and drainage pipes. Home ranges typically span one to four kilometres of waterway, with each individual maintaining a network of burrows and resting spots along the bank.
What They Eat
The rakali is a carnivore with a broad and opportunistic diet. Fish, crustaceans, freshwater mussels, insects, frogs, bird eggs, and occasionally small waterbirds all feature on the menu. One of the more remarkable items is the cane toad — an invasive pest lethal to most native predators. Rakali have learned to flip toads onto their backs and consume only the non-toxic internal organs, neatly avoiding the poisonous skin glands. This behaviour makes the rakali one of very few native animals capable of exploiting cane toads as a food source.
Feeding typically happens at dawn and dusk, when rakali swim along the water's edge in a characteristic V-shaped wake. Prey is brought ashore and eaten on flat surfaces such as logs or rocks, leaving behind distinctive middens — piles of shells and crayfish remains — that are a reliable sign of rakali activity. During winter, when animal prey is less abundant, rakali supplement their diet with plant material. Their droppings also play a broader ecological role: by dispersing fungal spores, rakali help distribute the mycorrhizal fungi that support native plant growth along riverbanks.
Breeding and Family Life
Rakali breed primarily in spring and summer in southern Australia, though in warmer northern regions breeding can occur year-round when conditions are favourable. After a gestation period of 33 to 41 days, a female gives birth to a litter of between three and seven young — with three to four being most typical in wild populations.
Newborn rakali are born blind and helpless inside a burrow lined with dry grass, reeds, or other vegetation. The mother nurses her pups for approximately four weeks, after which they begin to eat solid food. However, the young do not immediately strike out on their own — they remain with their mother for several more weeks, learning the skills they will need to survive. Young females can sometimes begin breeding at less than six months of age, though most reach sexual maturity closer to eight months. Rakali are solitary animals outside of breeding and pup-rearing, and their typical lifespan in the wild is three to four years.
Cultural and Historical Significance
The name rakali comes from the Ngarrindjeri people of South Australia, and its adoption as the preferred common name in recent decades reflects a broader effort to honour Indigenous knowledge and replace colonial-era terminology. For many Aboriginal communities, the rakali carries deep symbolic meaning — representing the connection between saltwater and freshwater country, and embodying qualities of playfulness, resilience, and renewal.
The rakali features in contemporary Indigenous art, including the striking Baanj Dayang (Rakali) Wilam sculpture created by Aunty Kim Wandin and Christine Joy, which depicts a pair of rakali playfully emerging from and returning to the water. The sculpture is a celebration of both the animal and the cultural knowledge surrounding it.
Historically, the rakali faced significant pressure from the fur trade. Large numbers were trapped and killed through the 1930s and 1940s, and the species remained subject to destruction permits until 1957 — well beyond the date of formal protection — followed by licensed hunting seasons until 1967. Since then, populations have recovered substantially, though the legacy of that period serves as a reminder of how quickly human activity can affect even a resilient native species.
Conservation Today
Nationally, the rakali is listed as Least Concern under Australian wildlife legislation, and its broad distribution suggests a generally stable population. However, the picture is more complicated at a local level. In the Wheatbelt region of Western Australia, the species is considered Near Threatened due to the salinisation of freshwater systems — a consequence of broad-scale land clearing that has raised groundwater salt levels to the point where many waterways can no longer support the plants and animals that depend on them.
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