Cane toads in Australia
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The cane toad (Bufo marinus) is an invasive species in Australia. The cane toad is the largest species in the family Bufonidae. Adult cane toads are usually heavy-built and weigh an average of up to 1.8 kg. (4 lbs.). Their size may vary from 15–23 cm.(4-9 in.) and their skin is warty. The coloration on their back and sides may vary from olive-brown or reddish-brown, gray, and yellow while their bellies are semi-yellow or semi-white with darker mottling. Their body is round and flat, has prominent corneal crests, and light middorsal stripes. Their front feet are unwebbed, but their back feet have tough, leathery webbing. Cane toads have short legs and a ridged bony head that extends forward from their eyes to their nose. Behind their ears lie the parotid glands, which usually causes their head to appear swollen. These glands are used for defense against predators. The parotid gland produces milky toxic secretion or poison that is dangerous to many species. This venom primarily affects the functioning of the heart. Envenomation is painful, but is usually not fatal for humans. However, it does have some effects, such as burning of the eyes and hands, and skin irritation. An adult cane toad (Bufo marinus).
1 Invasive species
2 Introduction and spread
3 Ecological effects
3.1 Predator effects
3.2 Methods to control invasion
4 In popular culture
5 See also
7 Further reading
8 External links
The cane toad in Australia is regarded as an exemplary case of a "feral species"—others being rabbits, foxes, cats, and Giant Mimosa. Australia's relative isolation prior to European colonisation and the industrial revolution—both of which dramatically increased traffic and importation of novel species—allowed development of a complex, interdepending system of ecology, but one which provided no natural predators for many of the species subsequently introduced. The recent, sudden inundation of foreign species has led to severe breakdowns in Australian ecology, after overwhelming proliferation of a number of introduced species for which the continent has no efficient natural predator or parasite, and which displace native species—in some cases these species are physically destructive to habitat as well. Cane toads have been very successful as an invasive species, having become established in more than 15 countries  within the past 150 years. The Australian Government placed cane toads in the Environment Protection and Biodiversity Conservation Act 1999 as a "key threatening process"  Introduction and spread
A young cane toad.
Native to Central and South America, Cane toads were introduced to Australia from Hawaii in June 1935 by the Bureau of Sugar Experiment Stations in an attempt to control the native cane beetle (Dermolepida albohirtum). These beetles are native to Australia and they are detrimental to sugar cane crops, which are a major source of income for Australia. Adult cane beetles eat the crop's leaves, but the main problem is the larvae, who feed on the roots. Adult cane beetles have a heavy exoskeleton and their eggs and larva are often buried underground, making them difficult to exterminate. Furthermore, conventional methods of pest control, such as pesticide use, would eradicate harmless species of insects as well, making it an unsatisfactory method.
The cane toads bred immediately in captivity, and by August 1935 more than 102 young toads were released in areas around Cairns, Gordonvale and Innisfail in northern Queensland. More toads were released around Ingham, Ayr, Mackay and Bundaberg. Releases were temporari...