Featured Research

from universities, journals, and other organizations

Salt water alone unlikely to halt Burmese python invasion

Date:
January 6, 2012
Source:
United States Geological Survey
Summary:
Invasive Burmese python hatchlings from the Florida Everglades can withstand exposure to salt water long enough to potentially expand their range through ocean and estuarine environments.

A Burmese python (Python molurus) peeks over the head of an alligator that holds the python's body in its mouth in Everglades National Park.
Credit: Lori Oberhofer, National Park Service

Invasive Burmese python hatchlings from the Florida Everglades can withstand exposure to salt water long enough to potentially expand their range through ocean and estuarine environments, according to research in the latest issue of the Journal of Experimental Marine Biology and Ecology.

This recent study, based on lab experiments conducted by researchers from the U.S. Geological Survey, provides initial evidence that pythons may be able to survive in marine and estuarine environments such as bays, inlets and open seas. The results raise concerns that the invasive constrictor may invade nearby islands, such as the Florida Keys, said Kristen Hart, a USGS research ecologist and lead author of the study.

"Because reptiles, in general, have poor salinity tolerance, it was hoped that salt water would naturally hinder pythons' ability to expand their range beyond the Everglades," Hart said." Unfortunately, our results suggest salt water alone cannot act as a reliable barrier to the Everglades python population."

Before the study, Burmese pythons had been found in brackish margins of the Everglades, the expansive and predominantly freshwater wetland that is home to the only known wild-breeding population of Burmese pythons in the United States. Yet, no information was available to indicate how long the snakes could persist in saline environments.

The issue of salinity tolerance is critical for understanding the risks of the giant constrictors spreading beyond the Everglades, given the Everglades location on the southernmost end of the South Florida peninsula.

"The fact that this study has ruled out one of the most hoped-for forms of physical barriers, salt water, as preventing the spread of invasive pythons in Florida puts even more onus on human action to prevent the spread of these damaging reptiles," explained USGS director Marcia McNutt. "This study demonstrates the distinct possibility that pythons could spread to new suitable habitats one estuary at a time."

In the lab, researchers tested how long hatchling pythons could survive with only salt water to drink. They found that, when given access only to water with salinity levels equivalent to full marine water, hatchling pythons straight out of their eggs lived about a month. At salinity levels comparable with estuaries, the hatchlings survived about five months.

The USGS research demonstrated, however, that varying salinity levels did affect the snakes, as reflected in significant survival differences between pythons exposed to freshwater, marine, and estuarine salinities in the lab. However, because hatchlings are considered the most vulnerable stage of the python's life, it's likely that adult snakes could persist even longer in saltwater environments, Hart and her colleagues noted.

By comparison, pythons in the study displayed a saltwater tolerance level near that of the native mangrove snake, a salinity-tolerant native snake found in high-salinity environments in and around the Everglades.

Although the study didn't account for the effect that access to food in saltwater environments would have on survival, lab conditions were designed to provide a conservative estimate of snake tolerance to salinity, by not allowing for the possibility that snakes could access freshwater from rain.


Story Source:

The above story is based on materials provided by United States Geological Survey. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kristen M. Hart, Pamela J. Schofield, Denise R. Gregoire. Experimentally derived salinity tolerance of hatchling Burmese pythons (Python molurus bivittatus) from the Everglades, Florida (USA). Journal of Experimental Marine Biology and Ecology, 2012; 413: 56 DOI: 10.1016/j.jembe.2011.11.021

Cite This Page:

United States Geological Survey. "Salt water alone unlikely to halt Burmese python invasion." ScienceDaily. ScienceDaily, 6 January 2012. <www.sciencedaily.com/releases/2012/01/120104153741.htm>.
United States Geological Survey. (2012, January 6). Salt water alone unlikely to halt Burmese python invasion. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2012/01/120104153741.htm
United States Geological Survey. "Salt water alone unlikely to halt Burmese python invasion." ScienceDaily. www.sciencedaily.com/releases/2012/01/120104153741.htm (accessed September 17, 2014).

Share This



More Earth & Climate News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Researchers Explore Shipwrecks Off Calif. Coast

Researchers Explore Shipwrecks Off Calif. Coast

AP (Sep. 16, 2014) Federal researchers are exploring more than a dozen underwater sites where they believe ships sank in the treacherous waters west of San Francisco in the decades following the Gold Rush. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Isolated N. Korea Asks For International Help With Volcano

Isolated N. Korea Asks For International Help With Volcano

Newsy (Sep. 16, 2014) Mount Paektu volcano in North Korea is showing signs of life and there's not much known about it. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins