Changing Planet

Snake populations show worldwide decline

Adding to the crushing evidence of global species decline is a new study by an international group of scientists that snakes may now also be in retreat. The disappearance of such top predators may have serious consequences for the functioning of many ecosystems, scientists warn.

Newly published data from the UK, France, Italy and Nigeria provides evidence that a number of snake species populations declined synchronously over a four-year period, UK researchers said today.

The research, published in the journal Biology Letters, was led by Chris Reading from the Centre for Ecology & Hydrology (CEH) in collaboration with colleagues from Italy, France, Nigeria and Australia. CEH is a public-sector research center that is part of the UK’s Natural Environment Research Council (NERC), which seeks to deliver independent research, survey, training and knowledge transfer in the environmental sciences to advance knowledge of Earth as a complex, interacting system.

“Long-term studies have previously revealed population declines in fish, amphibians, reptiles, birds and mammals,” CEH said in a statement posted on its website, and reported by several major news organizations, including the BBC.

“Many of these declines are a global phenomenon whose causes may vary but are often unclear. Among reptiles, snakes are top predators and therefore a decline in their numbers may have serious consequences for the functioning of many ecosystems,” CEH noted.

“The new research examined long term datasets from 17 snake populations from the UK, France, Italy, Nigeria and Australia. The data was collected between 1987 and 2009. Record lengths for individual species ranged from 13 to 22 years. All data sets covered the period 1997 to 2008.”

“This is the first documented evidence from anywhere in the world that snake populations may be declining. Of 17 snake populations (11 species), 11 (8 species) from tropical (Nigeria), Mediterranean (Italy) and temperate (France and the UK) climates declined synchronously and over a period of about four years between 1998 and 2002,” Reading said.

“Although we do not know the cause of these observed declines we wish to alert snake ecologists to what appears to be happening and to stimulate further research.”

The smooth snake, Coronella austriaca, is Britain’s rarest snake, and one of only three snake species present in the UK. It is restricted to the lowland heaths of southern England. The smooth snake, which is found in the UK, is among those showing decline, CEH said.

Posted by David Braun

Forty years in U.S., UK, and South African media gives David Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. He has 120,000 followers on social media. David Braun edits the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. Follow David on Facebook  Twitter  LinkedIn
  • Peter Grist

    I have been observing snakes, protecting snakes and keeping snakes for many many years. I have a great interest in protecting snakes. For the past two years I have noted a steep decline in snake populations and this decline is not apparent to any particular species. Certainly the cobra’s seem to be affected also Boomslangs and Puff Adder populations are definitely in decline. I mention these particular snakes as they are normally reasonably visible and I get more reports about them. There is no doubt either in my mind that this decline affects all our snake species here in South Africa. I am extremely concerned and I am talking about this matter on local radio tomorrow 12/04/2013

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