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| Burmese Python |
A team of researchers compared the distribution of mammals before and after the pythons were frequented these places.
In an article published in the Journal of the Academy of Sciences of the USA, the researchers report that the number of observations in some mammals has decreased by 90%.
The national park covers 25% of the original Everglades - an area of tropical lowland wetlands in southern Florida. Over the last century drained marshes intensively in order to use the land for economic purposes.
As in South Florida bred Burmese pythons, is not known. It is known that many of the Pythons were imported into the United States for commercial purposes.
Once out of captivity into the wild, pythons, in the absence of natural enemies, were able to breed highly.
tip of the iceberg
In 2000, the population of pythons in the Everglades has been recognized as stable. Prior to that, for twenty years, reports of meetings with them were quite disparate.
Has now been established that the pythons in South Florida live in an area of thousands of square kilometers. How many of them are exactly known, but the number of pythons caught in the Everglades in 2009, reached nearly 400, while growing with each passing year. (In 2010, however, there was a slight decrease in this number due to cooling.)
"The population of any snake you can see only a small fraction of their actual numbers," - explains one of the authors, Professor Davidsonovskogo College in North Carolina, Michael Dorcas.
The professor said in reserve Everglades dens were sverhhischnikami, being at the top of the food chain. "But this should not be here" - he adds.
"We have documented how pythons eat alligators. Also, we have documented, as alligators eating pythons. It depends on who during their meeting turns out to be bigger," - said in an interview with Dorcas BBC BBC.
In early January, Interior Secretary Ken Salazar announced that the U.S. is preparing to introduce a ban on the import of Burmese pythons. However, according to some observers, this step was late for about 30 years.
In the ambush
Professor Dorcas and his colleagues studied data on deaths of animals under the wheels of cars from 1993 to 1999, as well as gathering information about detection of live or dead animals during night-time observations in 1996-1997.
They then compared these data with similar studies conducted between 2003 and 2011, when the population of pythons was considered settled.
"The population of any snake you can see only a small fraction of their actual numbers," - explains one of the authors, Professor Davidsonovskogo College in North Carolina, Michael Dorcas.
The professor said in reserve Everglades dens were sverhhischnikami, being at the top of the food chain. "But this should not be here" - he adds.
"We have documented how pythons eat alligators. Also, we have documented, as alligators eating pythons. It depends on who during their meeting turns out to be bigger," - said in an interview with Dorcas BBC BBC.
In early January, Interior Secretary Ken Salazar announced that the U.S. is preparing to introduce a ban on the import of Burmese pythons. However, according to some observers, this step was late for about 30 years.
In the ambush
Professor Dorcas and his colleagues studied data on deaths of animals under the wheels of cars from 1993 to 1999, as well as gathering information about detection of live or dead animals during night-time observations in 1996-1997.
They then compared these data with similar studies conducted between 2003 and 2011, when the population of pythons was considered settled.
It was found that the number of detected raccoons and possums in that time has fallen by about 99%. The number of meetings with the white-tailed deer decreased by 94.1%, and at a trot - 87.5%.
In the latter study did not find a single rabbit and not a single fox. In this case it is most often the rabbits are among the victims of cars, according to a study 1993-1999.
As documented, researchers, most of these species fall into the diet of pythons that inhabit the Everglades Park.
Indeed, rabbits and opossums are often looking for food at the water's edge, where they become easy prey for the pythons, who wait in ambush for them.
The number of observations for rodents, coyotes and Florida panthers have increased slightly, but the total number of observations is low.
They also found that reducing the population of mammals coincides geographically with the spread of Burmese pythons. Where there were only pythons, there are many other animals, and the borders of their distribution mammals are found in abundance.
In the latter study did not find a single rabbit and not a single fox. In this case it is most often the rabbits are among the victims of cars, according to a study 1993-1999.
As documented, researchers, most of these species fall into the diet of pythons that inhabit the Everglades Park.
Indeed, rabbits and opossums are often looking for food at the water's edge, where they become easy prey for the pythons, who wait in ambush for them.
The number of observations for rodents, coyotes and Florida panthers have increased slightly, but the total number of observations is low.
They also found that reducing the population of mammals coincides geographically with the spread of Burmese pythons. Where there were only pythons, there are many other animals, and the borders of their distribution mammals are found in abundance.
However, those who have been breeding and collecting pythons do not agree with the fact that tropical snakes are too great a threat to south Florida ecosystem, and assert that such a ban will cause significant damage to multimillion-dollar business.
Although the ban no longer be able to reverse the situation in southern Florida, where these reptiles are already firmly established, a professor of Dorcas hopes that it will help prevent their spread to other appropriate for their ecological niches in the U.S. - such as southern Louisiana and south Texas.
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