Australian Journal of Zoology Australian Journal of Zoology Society
Evolutionary, molecular and comparative zoology

Geographic range, population structure and conservation status of the green python (Morelia viridis), a popular snake in the captive pet trade

David Wilson A B C and Robert Heinsohn A
+ Author Affiliations
- Author Affiliations

A Fenner School of Environment and Society, Australian National University, Canberra, ACT 0200, Australia.

B Present address: School for Tropical and Marine Biology, James Cook University, Townsville 4811, Australia.

C Corresponding author. Email:

Australian Journal of Zoology 55(3) 147-154
Submitted: 12 September 2006  Accepted: 15 May 2007   Published: 28 June 2007


Accurate knowledge of distribution and population size is required for effective conservation and management of wild species. Here we report on the first estimates of the distribution and density of the green python (Morelia viridis), an iconic rainforest species widely kept in captivity. We used climatic modelling to predict its distribution in Papua New Guinea, and both climate and vegetation mapping to predict its Australian distribution. We used mark–recapture methods to estimate the density and population structure of green pythons at Iron Range, northern Australia. Bioclimatic analyses suggested that there is extensive climatically suitable habitat in Papua New Guinea (≥200 000 km2), but very little in Australia (~300 km2). However, use of vegetation maps increases the predicted suitable area of occupancy in Australia to 3127 km2, including nine regional ecosystems. Density estimates at Iron Range were 4–5 ha–1 in the complex vine forest regional ecosystem; however, only half of these were mature adults. The large predicted area of occurrence and the high density in the one intensively studied area suggest that the species is not vulnerable to extinction in the short term. However, more studies are needed in both New Guinea and Australia, especially to quantify the impact of harvesting green pythons for the pet trade.


We thank all the people who helped search for specimens in the field, especially K. and A. Goetze, S. Legge, S. Murphy, B. Robinson, E. Sobey and K. Wilson. K. Nissen and J. Stein helped to generate maps. This research was funded by the Australian Geographic Society, National Geographic Society and the Hermon Slade Foundation. Appropriate permits were issued by the Queensland Environmental Protection Agency (WITK00337502) and the Australian National University (C.RE.24.02 and 27.02).


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Appendix 1.  Details of locations in Papua New Guinea used in the BIOCLIM prediction of the distribution of the green python (Morelia viridis) in Papua New Guinea

Appendix 2.  Details of locations in Australia used in the BIOCLIM prediction of the distribution of the green python (Morelia viridis) in Australia

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