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Burmese pythons (''Python bivittatus'') are native to Southeast Asia. However, since the end of the 20th century, they have become an established breeding population in South Florida. Although Burmese pythons were first sighted in Everglades National Park in the 1980s, they were not officially recognized as a reproducing population until 2000.〔Meshaka, W. E. Jr., B. P. Butterfield, and J. B. Hauge. 2004. The exotic amphibians and reptiles of Florida. Malabar, FL: Krieger Publishing.〕 Since then, the number of python sightings has exponentially increased with over 300 annual sightings from 2008 to 2010.〔Dorcas, M. E., J. D. Willson, R. N. Reed, R. W. Snow, M. R. Rochford, M. A. Miller, W. E. Mehsaka, Jr., P. T. Andreadis, F. J. Mazzotti, C. M. Romagosa, and K. M. Hart. 2012. Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park. Proceedings of the National Academy of Sciences 109:2418-2422.〕 Burmese pythons prey on a wide variety of birds, mammals, and crocodilian species occupying the Everglades.〔Snow, R. W., M. L. Brien, M. S. Cherkiss, L. Wilkins, and F. J. Mazzotti. 2007b. Dietary habits of the Burmese python, Python molurus bivittatus, in Everglades National Park, Florida. Herpetological Bulletin 101:5-7.〕〔Dove, C. J., R. W. Snow, M. R. Rochford, and F. J. Mazzotti. 2011. Birds consumed by the invasive Burmese python (Python molurus bivittatus) in Everglades National Park, Florida, USA. The Wilson Journal of Ornithology 123:126-131.〕 Pronounced declines in a number of mammalian species have coincided spatially and temporally with the proliferation of pythons in southern Florida, indicating the already devastating impacts upon native animals.〔 Although the low detectability of pythons makes population estimates difficult, most researchers propose that at least 30,000 and upwards of 300,000 pythons likely occupy southern Florida and that this population will only continue to grow.〔Snow, R. W., K. L. Krysko, K. M. Enge, L. Oberhofer, A. Warren-Bradley, and L. Wilkins. 2007a. Introduced populations of Boa constrictor (Boidae) and Python molurus bivittatus (Pythonidae) in southern Florida. Pp 416-438. In R. W. Henderson and R. Powell (Eds.). Biology of the Boas and Pythons. Eagle Mountain, UT: Eagle Mountain Press.〕 The importation of Burmese pythons was banned in the United States in January 2012 by the U.S. Department of the Interior.〔U.S. Fish and Wildlife Service. 2012. Salazar announces ban on importation and interstate transportation of four giant snakes that threaten Everglades. U.S. Fish and Wildlife Service Press Release. Jan 17 2012.〕 However, the lack of effective control methods for the already-established reproducing population necessitates better management of a potentially devastating invasive species. ==The Everglades and Burmese pythons== The Everglades is a region of subtropical wetlands comprising the lower third of the Florida peninsula. Only 25% of the original Everglades remains, protected within Everglades National Park (ENP). The climate of South Florida and the location of the Everglades, surrounded by a metropolitan area to the east, Naples to the west, and Florida Bay to the south, make it particularly vulnerable to infestations of exotic species. Miami, in particular, is the hub for trade in exotic pets within the United States. Although the exact origin of Burmese pythons in the Everglades is unknown, it is likely that many were once pets released by owners who found them too difficult to care for.〔Dorcas, M. E., and J. D. Willson. 2011. Invasive pythons in the United States: ecology of an introduced predator. Athens, GA: University of Georgia Press.〕 An evaluation of the genetic structure of Burmese pythons sampled from Everglades National Park determined that the population is genetically distinct from pythons sampled in the native range, but within the Everglades population, there is little genetic diversity. This finding either indicates that the python population is freely interbreeding or corroborates the hypothesis that the individuals originate from a specific source population such as the pet trade.〔Collins, Timothy M., Barbie Freeman, and Skip Snow. “Final Report: Genetic Characterization of Populations of the Nonindigenous Burmese Python in Everglades National Park.” Final Report for the South Florida Water Management District. Department of Biological Sciences, Florida International University, Miami, Florida, 2008.〕 Estimating the population of Burmese pythons in the Everglades is challenging because of the secretive nature of this species and the limited ability to conduct traditional mark-recapture assessments.〔Dorcas, M. E. and J. D. Willson. 2009. Innovative methods for studies of snake ecology and conservation. In S. J. Mullin and R. A. Seigel (Eds.). Snakes: ecology and conservation. Ithaca, NY: Cornell University Press.〕 Namely, it is counterintuitive to the primary goal of python removal to return captured pythons to the wild. Furthermore, the low detectability of pythons means that even if mark-recapture studies could be conducted, they would require a greater research effort than is currently possible. Pythons spend a majority of their day in hiding, whether in burrows or aquatic habitats, and one study indicated that even seasoned herpetologists showed only a 1% efficacy in detecting pythons housed in a seminatural environment.〔Dorcas, M. E. and J. D. Willson. 2013. Hidden giants: problems associated with studying secretive invasive pythons. In: W. Lutterschmidt (ed.), Reptiles in Research: Investigations of Ecology, Physiology, and Behavior from Desert to Sea. Nova Science Publishers, Inc., Hauppauge, NY.〕 Consequently, estimates of python populations range from at least 30,000 to more than 300,000.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Burmese pythons in Florida」の詳細全文を読む スポンサード リンク
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