Fox News reported Friday that a
tour guide in the Everglades was in the middle of a tour when he spotted a
python in the water. He then proceeded to hop off the boat and with the help of
another man wrestled and eventually killed the ten foot python. This incident
has been just one of many such incidents involving the invasive python species,
Python molurus bivittatus, occurring
in the Florida Everglades. In fact, these incidents have become such a problem
that they have many worried that the invasive species may spread beyond the Everglades
where they are thriving and wreak havoc on other ecosystems. In an article
entitled Can invasive Burmese pythons
inhabit temperate regions of the southeastern United States? Dorcas et al. attempt to discover
whether these invasive pythons could survive and thrive in South Carolina and
other regions in the southern United States.
This article was of particular
interest to me as I am a resident of South Carolina and find the idea of ten
feet long Burmese pythons in my back yard kind of alarming. Furthermore, I have
a particular interest in the spread of invasive species and prevention and
preemptive measures.
The actual study was performed in a
semi-natural enclosure in Aiken, South Carolina. South Carolina was chosen
because of its immediate proximity to Florida and its similar climate and
vegetation. What the researchers focused on however, was the one way South
Carolina’s climate differs from southern Florida, and that is the potential for
sub-freezing weather during the colder winter months. They monitored the snakes
body temperatures, behaviors, and habitat use while they were kept in the
enclosure during increasingly cold temperatures.
The snake-proof enclosure was
surrounded by a fence with a large pond in the middle. The pond had a shallow
end and a deep end and there were 4 large brush piles in the enclosure. Two of
the brush piles extended into the pond. There were several trees in the
enclosure and 4 artificial underground burrows . Ten male pythons captured at
Everglades National Park were released into this enclosure in June 2009. They
had radiotransmitters and microdataloggers surgically implanted within them to
record body temperatures hourly and to assist in locating the snakes for observations
and feedings. The pythons were fed pre-killed prey weekly from June until
mid-October when the cooler weather began to set in. The pythons were monitored
for location, behavior and habitat three times a week via the surgically
implanted transmitter. All snakes died during the study from the cold weather,
most from failure to seek appropriate shelter as the temperature rapidly
dropped, others that managed to take refuge in appropriate shelter below ground
in the artificial burrows eventually died either when they left the burrows, or
when an uncharacteristically cold patch of weather, even for South Carolina,
hit in late December to mid-January. When researchers at the University of
Georgia’s College of Veterinary Medicine performed autopsies on the dead snakes
they found no signs of respiratory infections, supporting the researcher’s
beliefs that the snakes all died from hypothermia.
However, the scientist performing
the study did conclude that while all snakes did die over the course of the
winter from the cold temperatures, most managed to survive for extended periods
of time in weather much colder than that of southern Florida. They also
emphasized that this winter was much colder than most winters in South Carolina
and that if the snakes had deeper refuges and normal South Carolina winter
temperatures they may be able to expand their range to South Carolina and other
southeastern states.
Dorcas, M.E., Wilson, J.D., Gibbons, J.W., (2011) Can
invasive Burmese pythons inhabit temperate regions of the southeastern United
States? Biological Invasions 13:
793-802.
1 comment:
Very interesting and applicable research - thanks for sharing!
Post a Comment