The Mighty Pythons of Florida
There have been many invasive species such as the rabbit in Australia. Now we have a carnivorous threat: the python who is literally eating Florida. Introduced Burmese pythons are firmly established in southern Florida, where they pose a serious threat to native wildlife. Burmese pythons, are native to Southeast Asia and can reach lengths greater than 20 feet. Pythons are long-lived (15 — 25 years), behavioral, habitat, and dietary generalists that are capable of producing clutches of up to 107 eggs. One new study, the first to document the ecological impacts of this invasive species, strongly supports that animal communities in this 1.5-million-acre park have been markedly altered by the introduction of pythons within 11 years of their establishment as an invasive species. Mid-sized mammals are the most dramatically affected, but some Everglades pythons are as large as 16 feet long, and their prey have included animals as large as deer and alligators.
The Burmese Python is the largest subspecies of the Indian Python and one of the 6 largest snakes in the world, native to a large variation of tropic and subtropic areas of Southern- and Southeast Asia. They are often found near water and are sometimes semi-aquatic, but can also be found in trees.
Burmese pythons are frequently kept as pets in the United States and apparently some were intentionally released or escaped in southern Florida during the last few decades. Pythons are now firmly established and reproducing within Everglades National Park and its vicinity and pose a serious threat to native wildlife.
Python populations in Everglades National Park have increased exponentially since the 1990’s and are expanding into the Keys and northward up the Florida Peninsula.
Predictive models based on climate indicate that suitable habitat for pythons exists across most of the southeastern United States1. However, other studies have suggested limited range expansion possibilities for pythons2 resulting in considerable debate regarding the risk this species poses to the southeastern United States.
The most severe Florida wildlife declines, including a nearly complete disappearance of raccoons, rabbits and opossums, have occurred in the remote southernmost regions of the park, where pythons have been established the longest. In this area, populations of raccoons dropped 99.3 percent, opossums 98.9 percent and bobcats 87.5 percent. Marsh and cottontail rabbits, as well as foxes, were not seen at all.
The researchers collected their information via repeated systematic night-time road surveys within the park, counting both live and road-killed animals. Over the period of the study, researchers traveled a total of nearly 39,000 miles from 2003 to 2011 and compared their findings with similar surveys conducted in 1996 and 1997 along the same roadways before pythons were recognized as established in Everglades National Park.
Areas north of the park are more python free. In those areas, mammal abundances were similar to those in the park before pythons proliferated. At sites where pythons have only recently been documented, however, mammal populations were reduced, though not to the dramatic extent observed within the park where pythons are well established.
Python image via Wikipedia.