Study suspects sharp reduction in snake numbers in a variety of habitats in five countries is caused by habitat loss and prey. Many of the researchers in the U.K., France, Italy, Nigeria and Australia also found evidence of population crashes — a sudden decline followed by no sign of recovery.

The widespread disappearance of snakes will be one impact of climate change that some people may find hard to regret. But as vital predators in sensitive habitats such as rice fields, their decline will have wider ecological consequences, say scientists.

The first major study of the problem, published on Wednesday, will also be seen as another sign of the destruction of the natural world, which is causing growing concern about the loss of vital resources from rainfall to medicines. Scientists on three continents report “alarming” declines in snake numbers after monitoring 17 populations in a variety of habitats — something they believe could be part of a global phenomenon. Species in decline include the smooth snake (U.K.), asp viper (France and Italy), and royal python (Nigeria).

The paper, published in the Royal Society journal Biology Letters, reports 11 of the population groups declined sharply, while five remained stable, and one showed a weak sign of increase. Many of the researchers in the U.K., France, Italy, Nigeria and Australia also found evidence of population crashes — a sudden decline followed by no sign of recovery.

“The main importance of these findings is that snakes are top predator within the habitats they are found in and as such play a potentially important role in the functioning of many ecosystems,” said Chris Reading of the U.K.'s Centre for Ecology and Hydrology, who led the research. “For example they play an important role in pest control — small rodents [like] rats and mice — in areas such as paddies and sugar cane plantations.” — © Guardian Newspapers Limited, 2010