Common death adder
Common name: common death adder
Scientific name: Acanthophis antarcticus (Acanthophis = spine-snake (referring to the spine at the tip of the tail); antarcticus = southern)
Family: Elapidae (venomous snakes)
Conservation status: This species is listed as Vulnerable in Queensland (Nature Conservation Act 1992). It is ranked as a medium priority under the Department of Environment and Heritage Protection Back on Track species prioritisation framework.
The common death adder has a short, stout body and grows up to 70-100 cm in length, although the average length is 40 cm. The species has a large, triangular head with small and inconspicuous eyes. Body colouration varies and tends to be blackish to grey to rich reddish-brown. The body is marked with irregular dark-edged cross-bands and the underside is whitish with black or brown flecks. The thin rat-like tail ends in a curved soft spine and the tip is cream or black.
Habitat and distribution
The common death adder occurs from the Gulf region of the Northern Territory across to central and eastern Queensland and New South Wales, and through to the southern parts of South Australia and Western Australia. Once abundant in many areas, this species has experienced a dramatic reduction in numbers.
Within this range the species is found in a wide variety of habitats in association with deep leaf litter, including rainforests, wet sclerophyll forests, woodland, grasslands, chenopod dominated shrublands, and coastal heathlands.
Life history and behaviour
A sluggish terrestrial snake, the common death adder is diurnal and nocturnal, although night activity is dependent on temperature. The species is secretive and relies on cryptic colouration to avoid detection. It will ambush prey by resting coiled and motionless while half-buried in sand, soil or litter and twitches its tail to mimic the movement of a worm. This attracts the attention of potential prey. Its diet consists mostly of lizards and small mammals, and to a lesser extent, birds and frogs. As diet changes with age, young animals usually consume reptiles and frogs, whilst adults feed on small mammals and birds. The venom of the common death adder contains a highly toxic neurotoxin which causes paralysis. The snake can deliver the fastest strike of all the venomous snakes in Australia.
Males reach sexual maturity at 24 months and females at 42 months. Mating usually occurs in spring. However, females reproduce only every second year. Common death adder females give birth to live young, which are typically born in autumn. The number of young in a litter is usually between 10-20, but as few as two and as many as 42 have been recorded.
Major threats to this species are:
- inappropriate grazing and fire regimes, which can degrade and destroy their habitat and food sources
- poisoning by cane toads
- clearing of vegetation, including loss of habitat through coastal development.
Other threats to this species include road-kill, removal of woody debris and rocks that provide refuge, and habitat degradation by feral pigs.
- Encourage sustainable grazing regimes that will maintain areas of habitat for common death adder.
- Encourage micro-mosaic patch burning for fire regimes, which will allow common death adders to find refuge from fires in un-burnt patches.
- Protect reptile habitat on the stock route network and shire roadsides and reserves.
- Prevent the destruction and degradation of important habitat, through: identifying guidelines to protect habitat; appropriate zoning; identifying development alternatives and incentives to retain habitat; and, educating communities.
- Encourage the retention of fallen logs, leaf litter and rocks, to provide refuges for common death adder.
- Adopt a collaborative approach to reptile conservation and encourage involvement from government agencies, regional Natural Resource Management (NRM) bodies, industry groups, indigenous groups, landholders and the community.
What can you do to help this species?
- In areas of known and potential habitat, implement appropriate grazing regimes to alleviate grazing pressure.
- Avoid removing fallen logs, leaf litter and rocks in common death adder habitat as this disturbs and diminishes refuge sites.
- Become involved in community-based projects (e.g. fencing remnants to reduce grazing impacts, weed and feral predator control, reptile monitoring) and help protect habitat across a suite of land tenures, particularly on non-reserved lands.
- Help protect threatened reptiles by supporting integrated pest management activities which seek to address feral animal threats (e.g. pigs, cats and foxes).
Cogger HG, Cameron EE, Sadlier RA & Eggler P. 1993. The Action Plan for Australian Reptiles. Australian Nature Conservation Agency, Canberra.
Wilson S. 2005. A field guide to reptiles of Queensland, Reed New Holland, Sydney.
Wilson S and Swan G. 2003. A complete guide to reptiles of Australia. Reed New Holland, Sydney.