Also known as the Giant Neotropical Toad or the Marine Toad, this amphibian was originally native to Central and South America. However, in June of 1935, Cane Toads were brought over to Australia from Hawaii in an attempt to curb the growth of the native cane beetle. They bred immediately in captivity, and by August 1935 more than 102 young toads were released into areas around Cairns, Gordonvale, and Innisfail in northern Queensland. More toads were released Ingham, Ayr, Mackay, and Bundaberg. Since their release, the toads have rapidly multiplied and now number over 200 million in population. They also have been known to spread diseases affecting local biodiversity. The toads have spread their range through Queensland, reaching the border with New South Wales in 1978n and the Northern Territory in 1984. The long-term effects of toads on the Australian environment are difficult to determine. Precipitous declines in populations of the Northern Quoll have been observed after toads have invaded an area. There are a number of reports of declines in goanna and snake populations after the arrival of toads. For example, local populations of Varanus panoptes dropped by up to 90% when their habitat was invaded by cane toads. The preliminary risk assessment of cane toads in Kakadu National Park stated that the predation of the cane toad by native wildlife is the greatest risk to biodiversity. Other factors, such as competition with native wildlife for resources, and the predation of the cane toad on native wildlife, were considered much lower risk factors but requiring further study. Attempts have been made to make use of dead cane toads, which can number in the thousands and cause hygiene problems. This includes processing the carcasses into liquid fertilizers. Their skin can be made into leather, and novelty cane-toad purses made of the fore-body and abdomen are sometimes seen. Cane toads have also been known to be a significant source of food for humans in their native environment; cane toads are cooked by skinning them and removing the internal organs (including the poisonous glands), then roasting them. It has been said they are like chicken except with a drier taste. In Australian states where the cane toad is common, some 'sports' have developed, such as cane toad golf and cane toad cricket, where cane toads are used as balls. In April 2005, Dave Tollner, a Northern Territory Member of Parliament, called for legalisation of attacks on cane toads. This was criticized by many animal and conservation groups who claim freezing is a more humane way to kill cane toads than hitting them with cricket bats.
An invasive species that is affecting North America is the English ivy, or Hedera helix. Native to most of Europe and western Asia, it is labeled as an invasive species in many parts of North America, and its sale or import is banned in the state of Oregon. Like other invasive vines such as kudzu, H. helix can grow to choke out other plants and create "ivy deserts" in the United States. State and county sponsored efforts are encouraging the destruction of ivy in forests of the Pacific Northwest and the Southern United States. Its sale or import is banned in Oregon. Ivy can easily escape from cultivated gardens and invade nearby parks, forests and other natural areas. Ivy can climb into the canopy of trees in such density that the trees fall over from the weight, a problem which does not normally occur in its native range. In its mature form, dense ivy can destroy habitat for native wildlife and creates large sections of solid ivy where no other plants can develop. Many gardeners have found that the best solution for getting rid of English ivy is to cut the vines off the tree/wall/building, uproot it, and spread a layer of mulch over the ground for about two years so that the seeds cannot reestablish themselves in the ground. However, English ivy is very difficult to get rid of.
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