|A European red fox (Vulpes vulpes)|
This species is native to a very large area: Europe and virtually all of Asia, plus parts of North Africa and North America. They have been introduced to Mexico, Canada, the United States, and Australia. Due to the addition of this introduced range, the red fox is easily called "the most widely distributed carnivore in the world."
Numerous methods have been and continue to be used in attempts to control the red fox population, especially in Australia. Poisoning, shooting, fencing, and trapping have all been used, but recently there has been more concentration on trying to limit the foxes' abilities through baiting. These baits may include poison, vaccines, or something that effects fertility, which reduces the number of young born. In Australia, the poison used is derived from a native plant that native species can tolerate so as to only kill the invasive. Exclusion fencing can also quite useful if constructed in the right manner.
The red fox is on the list of the 100 World's Worst Invasives at #99.
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