A new and recent study performed by the United States Geological Survey (USGS) has predicted that hatchling Burmese pythons (Python bivittatus) collected from the Florida everglades can withstand exposure to salt water long enough to potentially expand their range through ocean and estuarine environments. According to USGS research ecologist and author of the study Kristen Hart, it is speculated that Burmese pythons are now capable of expanding their south Florida range to surrounding islands such as the Florida Keys.

Which begs the question: If Burmese pythons have been present in the Everglades since the 1980's, why haven't they been found in these areas already? Why then haven't naturally occurring populations of Burmese pythons in Southeast Asia made their way over to the Phillipines, Malaysia, Borneo, and Indonesia yet?

The Study

According to the new study, 24 hatchling, and 1 YoY Burmese pythons were collected for the study out of Everglades National Park, where each was housed individually in 75L plastic storage bins. One of three different water "treatments"; fresh water, brackish water, and salt water were then evenly distributed among the hatchlings (8 were subjected to each "treatment") while the single Yoy was subjected to marine treatment. Each "treatment" was provided in the form of 4 L plastic bins covering approximately 40% of the enclosure surface area, thereby allowing the snakes to voluntarily come into contact or avoid the "treatments" (more on that in a moment).

According to the results of the study, the mean (average) longevity for the snakes subjected to marine treatments was 32 days, with some animals perishing as early as 17 days. Dr. Warren Booth has stated it well: death= no further reproductive ability. The last animal subjected to marine treatments perished at 50 days. Only 2 hatchlings subjected to the brackish water treatment survived for more than 200 days, with mean being 156. The single Yoy subjected to a marine treatment survived throughout the study, but long turn effects and prognosis of the surviving snakes is not mentioned at all in the study.

More Shaky, Poorly Constructed "Science"?

The study may have been just released, but after reading it, I am already noticing several major flaws in it and yet even more poor quality "science" at play. The first, and perhaps foremost observation I have is that this "study" fails to accurately replicate prolonged long distance travel and/or survival in saline/marine environments; all experimental snakes in the study were provided access to dry land and were still given access to fresh water in the form of food items (in this case, mice) throughout the study. Thus, because of this, I suspect that survival rates for snakes housed in such brackish and marine "treatments" were prolonged significantly by the authors of this study.

The other consideration the "study" fails on is examining long term prognosis and survival of snakes subjected to brackish and marine treatments. Even if a Burmese python did manage to travel to one of the Florida Keys, or the Phillipines, what would be the long term survivability of said snake having been exposed to such saline environments for the prolonged periods of time needed to move across it? Such a preliminary study should require significant follow up and review in the months to come.

Undoubtedly we can expect more of the same in 2012 as we did in 2009. No doubt that this "study" and its predictions will splash far and wide in media headlines in the new year, and be used in the latest efforts to drum up speculative fears of widespread U.S. python invasion via ocean ways as well as support for a Federal Lacey Act listing of 9 boa and python species. One thing is for certain; this study will make for an appealing case to legislators and ambitious politicians alike looking to maintain their bids for upcoming re-election.

All in all, like the failed climate maps and other poor quality "science" put out by USGS projecting that Burmese pythons are capable of expanding their south Florida range across the southern third of the U.S. and deemed by a panel of 11 herpetologists and other scientists as "unscientific", I would likewise entirely expect this new "study" to be largely unconvincing to the majority of the herpetological community and failing to stand up to external scrutiny and review once it is made.

Here is a link to the USGS press release:
USGS Press Release