The negative impacts inflicted by exotic species on native species and ecosystems may only be exceeded by human-caused habitat destruction (Parker et al. 1999; Wilcove et al. 1998). In the USA, exotic species have played a role in the listing of 42% of the species protected by the Endangered Species Act (Stein and Flack 1996). Invasive species can be considered "pathogens of globalization" (Bright 1999) and Florida provides an ideal medium in which such pathogens can incubate. In fact, quantitative indicators for assessing non-native species situations are analogous to epidemiological descriptors of disease status in a population (Meyerson et al. 2008). Florida's subtropical climate, its major ports of entry for many wildlife species to the U.S. (both legal and illegal), its thriving $300 million captive wildlife industry, and its position in an area of destructive hurricanes that can release captive animals make the state especially susceptible to the introduction and establishment of a wide range of species (e.g. Corn et al. 2002, Hardin 2007). Moreover, Florida is isolated from land with similar climates, resulting in the state's native vertebrates typically originating in the southeast U.S. at the southern extremes of their range. Invaders to Florida therefore find relatively fewer native species to contend with than in most tropical/subtropical locations (Hardin 2007). Florida joins Hawaii as the two states with the most severe invasive species problems in the United States (U.S. Congress 1993, Corn et al. 2002). Notably, Florida has more introduced animals than any other region of the U.S. and also ranks high in this respect globally, with breeding populations of new vertebrate species regularly identified (SFWMD 2008).

The impacts from many introductions are unknown or not readily perceived by the public, while others are immediately apparent or have their negative potential revealed over time. Even highly prolific invasive species may fester for a considerable time before exhibiting an explosive expansion of their range (Shigesada and Kawasaki 1997). Management of an exotic species requires more than the recognition of a potential problem, it also requires a governmental/public motivation to address the problem. Invasive species often present novel control situations for managers, requiring the acquisition of biological knowledge and the development and testing of control technologies and strategies (see, for example, Engeman and Vice 2001).

The situation in Florida is best understood through a variety of examples. Given Florida's climate, it is no coincidence that a large proportion of the species discussed here are reptiles. Overall, the examples not only demonstrate the breadth of the terrestrial invasive vertebrate problems in the state, but they also show the diversity in resolve and response against the many species and the motivating factors.

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