Australia’s Ambush Predator The Common Death Adder
The common death adder (Acanthophis antarcticus) is one of Australia’s most dangerous and venomous snakes ranking high among the world’s deadliest snakes.
Despite its dangerous nature, this species is relatively widespread, found across Australia’s eastern and southern coasts, thriving in forests, grasslands, and woodlands. It’s called a “death adder” due to its highly effective ambush strategy and swift, deadly strike – traits that once made it synonymous with death in the eyes of early settlers.
Although called an ‘adder’, the common death adder is not actually related to the true European adders, which belong to the Viperidae family. This species belongs to the family Elapidae, which includes many of Australia’s other venomous snakes.
Scientific Classification
- Domain: Eukaryota
- Kingdom: Animalia
- Phylum: Chordata
- Class: Reptilia
- Order: Squamata
- Suborder: Serpentes
- Family: Elapidae
- Genus: Acanthophis
- Species: A. antarcticus
- Binomial Name: Acanthophis antarcticus (Shaw, 1802)
Distribution in Australia
The common death adder is a venomous serpent indigenous to Australia, ranking among the most toxic snakes both on the continent and worldwide. Its presence remains relatively widespread, although it faces growing threats from the invasive cane toad, which has been encroaching upon its habitat.
Danger to Humans
Equipped with large fangs and potent venom, death adders pose a significant risk to humans. Before antivenom became available, their bites were fatal in approximately 60% of cases.
If you’re bitten by a common death adder, seek immediate medical attention – its venom is highly toxic. Death adder venom contains neurotoxins that can cause paralysis by blocking nerve signals, which can lead to respiratory failure. Before the development of antivenom, most bites were fatal. Today, with prompt medical intervention, including antivenom administration and supportive care, most people survive, though symptoms can still be severe, including difficulty breathing, muscle weakness and possible long-term effects.
Taxonomy and Behaviour
First documented in 1802, this snake exhibits a unique predatory style. Unlike many other venomous snakes in Australia that actively hunt, the common death adder employs a sit-and-wait strategy, patiently ambushing frogs, lizards, and birds. They are more commonly encountered at night when they are moving between shelter sites. Being primarily nocturnal but can sometimes be active during the day.
Most snakes flee when frightened, but the death adder relies on its camouflage to remain motionless even when danger approaches. This behaviour can make it more likely for humans to accidentally step on or near the snake, increasing the risk of bites. Making the death adder particularly dangerous to those who enjoy bush-walking without noticing it hidden in leaf litter or undergrowth.
Description
The Common Death Adder stands out due to its distinct triangular-shaped head, a short and robust body, and a slender tail. These features make it quite recognisable.
It boasts a thick body adorned with bands of red, brown, and black, while its belly is typically grey, cream, or even pink. Male and female death adders differ in size, with males averaging 44 cm and females 58 cm. The snake can grow up to 100 cm in length.
Distinct from the common or European adder (Vipera berus), this species belongs to the Elapidae family, not the Viperidae, which do not inhabit Australia.
Habitat and Distribution
This snake is predominantly found along the eastern and southern coastal regions of Australia, including Queensland, New South Wales, and South Australia. It is less common in the Northern Territory and Western Australia, and has vanished from Victoria. Additionally, it is native to Papua. The death adder thrives in forests, woodlands, grasslands, and heaths, expertly camouflaging itself under loose leaf litter and debris.
Diet
This cunning predator dines primarily on small mammals and birds. Unlike its elapid relatives, the death adder remains motionless, often for days, hidden under leaves and debris, waiting to ambush its prey. It lures its victims by twitching its worm-like tail, and when an unsuspecting animal approaches, the snake strikes swiftly, delivering venom before waiting for the prey to die.
Reproduction
Females reproduce only every second year, in an unusual departure from most snakes, death adders give birth to live young. Litter sizes usually range from 2 to 42 offspring, records of litters over 40 are rare. The young are typically born in February or March.
Conservation Status
The common death adder faces challenges such as habitat destruction and the spread of invasive cane toads. These toads consume young death adders, and adult snakes that prey on them suffer from poisoning due to the toads’ toxic skin glands.
Aside from cane toads, other threats to the common death adder include trampling by livestock, predation by feral cats, foxes, and pigs, and accidental poisoning from consuming poisoned rodents like the house mouse.
The death adder is considered rare in some regions, being listed as “Rare” in Queensland and “Threatened” in Victoria, largely due to habitat destruction and other environmental pressures.
It has a formal international conservation status of “Least Concern” according to the International Union for Conservation of Nature (IUCN) version 3.1. This classification suggests that, despite its venomous nature, the species is not currently at significant risk of extinction.
