Following importation to the USA for the pet trade, it has become a serious invasive pest in the Florida Everglades, decimating local populations of native species.
WHAT’S IN A NAME?
Pythons comprise a family of non-venomous snakes found in Africa, Asia and Australia.
The family and genus name ‘Python’ is the anglicised version of the Greek ‘πύθων‘ (pythōn) who in Greek mythology was the serpent living at the centre of the earth.
The species name ‘bivittatus’ comes from Latin words ‘bi‘, meaning ‘2’ and ‘vittatus‘, meaning ‘banded’, possibly in reference to the prominent double line of scales forming an arrow shape on its head.
So the scientific name translates simply to ‘double-banded snake’.
WHERE DO THEY LIVE?
Burmese pythons are native throughout south and southeastern Asia, from eastern India and Nepal to southern China and the Indonesian islands of Java, Sulawesi Bali and Sumbawa. (see map)
They have adapted to a wide variety of habitats, including grassy marshlands and swamps, rocky foothills, river valleys and open jungles, but always near a permanent source of freshwater.
Fun Fact: Burmese pythons are excellent swimmers and can stay submerged for 30 minutes at a time!
Young pythons climb trees, but as they grow heavier they become ground dwellers.
Introduced into the United States as pets, a damaging invasive population has been established in south Florida, including in the World Heritage listed Everglades National Park.
WHAT DO THEY LOOK LIKE?
This is a heavy-bodied, strikingly patterned snake! The back has a base colour of pale brown or grey, with large reddish-brown blotches outlined in black. An arrow-shaped marking on top of the head points towards the nose. The belly is white, unpatterned and bordered by black spots.
Burmese pythons can grow to 5 metres long (16 ½ ft) n the wild, and can weigh over 75 kilograms (165 lb)! Females average slightly longer than males, and become heavier and bulkier.
Reports of individuals over 7 metres (23 ft) in length are unconfirmed.
Fun Fact: A snake named ‘Baby’ holds the record for the longest confirmed measurement of length at 5.74 m (18 ft 10 in). She lived at Serpent Safari in Illinois, and at the time of her death, aged 26, she weighed a massive 182.8 kg (403 lb), much greater than any other confirmed report!
WHAT DO THEY EAT?
Burmese pythons are apex predators, and are strictly carnivorous. They prefer small mammals, but as they grow larger are capable of eating larger animals such as deer, pigs and goats.
They also eat birds, amphibians and reptiles.
In Florida they are known to prey on American alligators!
Burmese pythons are ambush predators. If a prey animal comes within striking range it will lash out quickly, grabbing it with its sharp teeth and holding it with powerful jaws. It then coils its body around the victim and kills the animal by constriction, before swallowing it whole.
Contrary to popular belief, pythons do no ‘dislocate’ their jaws to swallow large prey. The bottom jaw is actually made up of two bones, separated by skin and tissue which can stretch to a width four times bigger than its skull. After the meal is consumed, the skin gradually snaps back into shape.
In order to digest prey that has been swallowed whole, the python’s stomach secretes large volumes of hydrochloric acid. Digestion takes about 8-14 days, but the python will typically fast for up to several months after a large meal!
REPRODUCTION
Burmese pythons are solitary for most of the year. During breeding season, between December and March, one or more males may mate with a single female.
Fun Fact: Burmese pythons in captivity have occasionally reproduced by parthenogenesis, in which a sex cell can develop without fertilization!
After about 3 months the female lays a clutch of eggs—typically fewer than 40, but occasionally as many as 80 to 100!
She incubates the clutch for about 2 months by wrapping herself around the eggs and twitching her muscles to increase the ambient temperature. After the eggs hatch, the babies are independent and receive no further care.
Burmese pythons reach sexual maturity by age 2 or 3, and can live for more than 20 years in the wild and 25 years in captivity.
STATUS IN THE WILD
The Burmese Python was most recently assessed for The IUCN Red List of Threatened Species in 2011 and listed as Vulnerable.
It has been listed as Critically Endangered in two major areas within its geographic range because of population crashes of up to 80% in a single decade.
In several countries it is harvested unsustainably for food, for the illegal pet trade, and for its skin which is used to make leather garments and drums.
They are also threatened by habitat loss as forests and marshlands are cleared for agriculture.
It is estimated that more than 30 000 Burmese pythons were exported to the United States since they were first brought in as exotic pets in 1980. Their importation into the USA was banned in 2012 by the US Department of the Interior.
INVASIVE SPECIES
There is now an established breeding population of Burmese pythons in southern Florida, the only area in the USA that remains frost-free all year round.
The first individuals were probably pets that had grown too large to handle and were released. Additionally, many escaped from a reptile breeding facility that was destroyed when Hurricane Andrew crossed Florida in 1992.
With their high rate of reproduction, rapid sexual development and longevity, and the lack of native predators, they rapidly proliferated into an injurious invasive species. Population estimates are difficult, but there may now be as many as 1 million pythons in south Florida!
The effect on the local ecosystems has been disastrous.
Burmese pythons prey on native species, outcompete them for food, and disrupt the physical environment. There have been severe declines in populations of native mammals such as raccoons, opossums, bobcats, marsh rabbits and foxes. In some areas of the Everglades, entire species have been eliminated.
Threatened species that have been identified as prey include little blue herons, roseate spoonbills, and big cypress fox squirrels.
In a grim demonstration of their impact on even the largest of native species, scientists in 2012 found a 5 ft (1 ½ m) long adult American alligator in the stomach of an 18 ft (5 ½ m) Burmese python!
The devastation in Florida is a stark reminder of the impact of introduced species on native animals. Here in Australia it is illegal to import, breed, keep as a pet or sell Burmese pythons.
BURMESE PYTHONS AT BILLABONG SANCTUARY
Only facilities with the appropriate licence from Biosecurity Queensland are allowed to keep Burmese pythons. Billabong Sanctuary has an approved management plan in place, and we are fortunate to have obtained two individuals from Australia Zoo—Nagani and Salazar. Nagani will be housed in the newly constructed exhibit on the Exotic Species Boardwalk.
Nagani, hatched in 2006, is a 4 metre (13 ft) long female, weighing 23 kilos (51 lb). Salazar, born in 2011, is a younger and smaller male—but still impressive in size!
Once they are settled in, we plan to bring Nagani out to the Reptile Pit where you will have the opportunity to pat them. No handling—it takes 3 or 4 experienced rangers to safely carry these magnificent reptiles!
Show times and patting opportunities will be published on our website and Facebook pages.
Further Reading
https://nre.tas.gov.au/wildlife-management/management-of-wildlife/wildlife-imports/species-risk-assessments/burmese-python-(python-bivittatus)
https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=2552
https://vpi.com/sites/default/files/Barker-et-al_CorrectPythonLengths_2.pdf
https://www.scientificamerican.com/article/heres-how-a-python-jaw-can-fit-a-whole-deer1/
https://www.iucnredlist.org/species/193451/151341916#assessment-information
Burmese pythons in Florida: A synthesis of biology, impacts, and management toolshttps://neobiota.pensoft.net/article/90439/ NeoBiota https://doi.org/10.3897/neobiota.80.90439