Exploring the Python Dichotomy

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A Tale of Two Populations: Burmese Pythons of Bangladesh May Be Dwindling in their Native Environment While Thriving as
Invaders Half a World Away in the Everglades

Author: Shahriar Caesar Rahman,

Department of Environmental Science, Independent
University, Bangladesh and Center for Advanced Research in Natural Resources
and Management (CARINAM), Bangladesh.


Burmese pythons (Python molurus
bivittatus)
in the Florida Everglades have been the subject of intensive scientific
study and media scrutiny in recent years as concern grows about their impact as
invaders. It is suspected that the non-native pythons pose a serious threat to
native ecosystems in Florida, not just in their current range but far beyond.
The impact of pythons and their potential range expansion in other parts of the
United States is not clearly understood, partly because of a lack of
knowledge concerning their ecology and behavior in their native range.

Half a world away, Burmese pythons
remain one of the least-studied python species on the planet. Despite their
tremendous popularity in the pet industry, Burmese pythons in native Asia are something of a mystery. Drastically understudied in almost all aspects of their
biology, very little is known about the Burmese python, their ecology, and
natural history in Asia.

  Enlarge PhotoSearching for pythons in the heart of Lawachara’s rainforest

Published knowledge on the ecology
and behavior of free-ranging Burmese pythons in their native range is limited
to studies of their basking and breeding behavior in Keoladeo National Park, Rajsthan, India; a 24-day radio telemetric study of a single individual in Hong Kong; and incidental natural history observations. Detailed field study on Burmese
pythons is long overdue.

With that in mind, our research team embarked on a field
study of Burmese pythons in Bangladesh’s Lawachara National Park in May of 2011
with initial financial support from The Orianne Society and The Explorers Club.

Both subspecies of Asian rock
pythons, Indian Python (Python molurus molurus) and Burmese Python (Python
molurus bivittatus
), occur in Bangladesh. Once common throughout the
country, pythons are now fragmented into small and disjunct populations. They
are now mostly found in the Sundarban mangrove forest in the southwest and the
mixed-evergreen forests in the northeast and southeast of the country.

  Enlarge PhotoAbandoned Burmese python nest

Habitat destruction is one major
cause of their decline. Indiscriminate killing — out of fear or for
consumption — is another.

Lawachara National Park, a 1,250
hectares mixed-evergreen forest, located in the northeast of Bangladesh, falls
within the Indo-Burma Biodiversity Hotspot, which supports some of the most
unique and diverse biota on the planet. Most of the original forest cover has
been altered or substantially removed by rotation since the early 1900s, with
only some small, remnant patches of primary forest left inside the park.

During our first year of study, we
conducted intensive field surveys in this forest-plantation mosaic landscape to
collect baseline data on the python population and create a base for a
longer-term ecological study. Our research team also spent hundreds of hours in
the field and systematically documented more than 500 individual snakes and
identified 35 snake species from Lawachara National Park and the surrounding
tea estates. Several of the snake species were recorded for the first time from
Bangladesh.

Despite the adversity herpetofauna
may be facing—from indiscriminate killing, road mortality, deforestation, and
degradation of the habitat—Lawachara appears to be a snake hotspot in this
region.

Surrounded by tea plantations and
human habitats on almost all sides, Lawachara pythons are opportunistically
captured and consumed by the indigenous tribal people living adjacent to the
forest. Pythons are also often found on the tea estates, particularly in
porcupine and pangolin burrows. During our survey, we found an abandoned python
nest as well as four python hatchlings in different parts of the tea
plantation, indicating that pythons use the plantation areas for breeding
purposes.

  Enlarge PhotoA python captured from a tea estate

This summer, we plan to implant
radio transmitters and miniature temperature loggers on several adult pythons
to collect data on movement, ranging patterns, and thermal preference of free-ranging
pythons.

One of our future research objectives is to answer some
important scientific questions: How do pythons react to thermal variation
throughout the year? How much time do they spend basking in winter, and do they
use different areas of their activity range in cool months versus warm months? How does thermal biology affect detection
probability?

The
knowledge gained from this study could be crucial for many reasons.  Any
information that sheds light on the natural history and ecology of pythons
could provide knowledge to help understand their impact on the Everglades and
potential range expansion in North America. Our study site in Bangladesh is at nearly the same latitude as southern Florida, which could allow for the collection
of useful comparative data to help understand the invasion process.

Also, Burmese
pythons are considered Endangered in much of their native range. The
lack of basic information makes conservation and
management decisions difficult at best, and possibly inappropriate. Collecting
information about their home-range size, habitat use, thermoregulatory behavior
(e.g. basking) and other aspects of life history will be vital for conservation
and management of this species in Bangladesh or anywhere in their native range.


This article is also featured in the first issue of Serpens, the newsletter of the IUCN Boa & Python Specialist Group. You can see the article and read more about Boas and Pythons in the following attached newsletter.