Snakes may be in decline worldwide: study

Jun 08, 2010
Distinct populations of snake species on three continents have crashed over the last decade, raising fears that the reptiles may be in global decline, according to a study published Wednesday.

Distinct populations of snake species on three continents have crashed over the last decade, raising fears that the reptiles may be in global decline, according to a study published Wednesday.

The pattern across the eight species monitored was alarmingly similar despite their geographical isolation, which points to a common cause such as , the researchers said.

Other factors known to play a role include habitat loss, pollution, disease, lack of and over-exploitation, either for food or trade.

The study showed that 11 of 17 snake populations in Britain, France, Italy, Nigeria and Australia dropped off sharply over a four-year period starting in the late 1990s.

"Our data revealed an alarming trend," the authors reported in the British Royal Society journal Biology Letters.

"Two-thirds of the monitored populations collapsed, and none have shown any sign of recover over nearly a decade since the crash. Unfortunately, there is no reason to expect a reversal of this trend."

are top among , and a sharp decline in their numbers would likely have serious consequences for many ecosystems.

Earlier studies have turned up dwindling numbers for certain species and in some regions, especially the .

But the new study presents the first evidence that snakes in the tropics are also in trouble.

Depending on the continent, population declines varied depending on sex, with females disappearing significantly more rapidly than males in most cases.

So-called 'sit-and-wait' foragers -- snakes that lie motionless, waiting for prey to come within striking distance -- are also more severely depleted in numbers than counterparts which are active hunters.

The fact that the declines observed happened in different corners of the globe over the same short time points to a single problem.

"We suggest that there is likely to be a common cause at the root of the declines, and that this indicates a more widespread phenomenon," the study concluded.

Explore further: Biologist reels in data to predict snook production

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User comments : 13

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xanderjones
4 / 5 (4) Jun 08, 2010
Alright you climate change naysayers, go ahead and have your rant on how they include it in every story.

Please. Go.
jsa09
2.7 / 5 (3) Jun 08, 2010
@xanderjones You are correct. It is completely insane to suggest climate change could have any significant effect on snake populations around the world in a 10 year period.

One would be better served in looking for something that has changed over that period of time.
Skeptic_Heretic
3.7 / 5 (3) Jun 08, 2010
@xanderjones You are correct. It is completely insane to suggest climate change could have any significant effect on snake populations around the world in a 10 year period.

One would be better served in looking for something that has changed over that period of time.

How about drought conditions due to global warming killing off their food supply (insects). If you're serious, then it's time for you to grow up, kid.
JohnnyB
5 / 5 (2) Jun 08, 2010
There will always be something for the nay sayers to cling to. It's like a religion. Even if there is proof say that cigarettes cause cancer, you will always have the guys who point to the 90yo who is fine. Some people make the world fit their ideas rather than the other way round.

It would be great if these guys were harmless but unfortunately most of them can vote.
Eric_B
5 / 5 (2) Jun 08, 2010
they vote and worse they run their mouths and infect others with their corporate-slave mentality drivel.

didn't they say the hole in the ozone didn't matter? since the people getting skin cancer and going blind on a normal summer day were "down there" in Chile, etc, it was of no concern to them.
ParadigmShift
5 / 5 (2) Jun 09, 2010
I have a feeling snake biodiversity is hit much more significantly over short periods of time due to habitat loss and human incursion more than anything else. Not limited to snakes, of course. The ongoing loss in biodiversity across the world is primarily anthropogenic (I know, that word stings).

Climate change would be a factor, but when it comes to biodiversity loss, clearing natural habitat and developing over it seems a much more effective way to eradicate species quickly.
Skeptic_Heretic
1 / 5 (1) Jun 09, 2010
they vote and worse they run their mouths and infect others with their corporate-slave mentality drivel.
That's the best part of freedom of speech. The faster we can get them in public and shoot down their laughable statements with fact the better off we are.

We just need to take the idiots, like Gore, who have little to no knowledge of reality and prevent them from speaking for us.
Skeptic_Heretic
1 / 5 (1) Jun 09, 2010
Excuse my statement above, I said "prevent" what I intended was to make plain that a man who states the core temp of the Earth is several million degrees is not within the bounds of factual or informational science on the topic at hand.
jsa09
not rated yet Jun 11, 2010
@ParadigmShift
I have a feeling snake biodiversity is hit much more significantly over short periods of time due to habitat loss and human incursion more than anything else. Not limited to snakes, of course. The ongoing loss in biodiversity across the world is primarily anthropogenic (I know, that word stings).

Climate change would be a factor, but when it comes to biodiversity loss, clearing natural habitat and developing over it seems a much more effective way to eradicate species quickly.


This was the point I was trying to make. I think I actually typed most of that in - must have lost it before I saved.

Urban development, roads, micro climate variation due to urbanization, pesticides etc all of these things would be significant killers of snakes in short time spans.
jsa09
not rated yet Jun 11, 2010
@Skeptic_Heretic and others. Your rush to flame other posts does not do you justice I hope, and lends one to wonder just how much independent thought your guys put in to what you read.

Suggesting that global droughts will occur due to Global warming is pretty lame. I know you can say it was just one example but I think it is more indicative or general attitude.

This article does appear to attribute things where we have cause and affect but climate change does not manifest in such a short time frame. Climate change takes time much greater time than a single decade unless it is happening at a rate 100's of times faster than even the most radical scientist will suggest.
Ronan
not rated yet Jun 11, 2010
Jsa09: Note the time frame, though. The late '90s...what happened then, climate-wise? Ah, yes; an El Nino year, with one of the highest average global temperatures ever recorded. Of course, correlation does not equal causation; I'm just pointing out that if one were looking for some climate-based way to explain a sudden drop in populations, a starting point for one's investigation does exist.

That said, it's interesting that ambush predators would fair less well than the wanderers. There might well be other causes for that, but it seems like ambush predators would be more vulnerable to poaching than the wanderers; surely an animal that sits around all day in the same spot would be easier to catch?
phlipper
not rated yet Jun 13, 2010
they vote and worse they run their mouths and infect others with their corporate-slave mentality drivel.

didn't they say the hole in the ozone didn't matter? since the people getting skin cancer and going blind on a normal summer day were "down there" in Chile, etc, it was of no concern to them.

Actually, that never happened. It was just more bad science from true believers.
http://tinyurl.com/2cjckgj

" Blind sheep in southern Chile were found to have common eye infections in no way associated with any putative increases in UV-B. And any serious effect on the immune system from an increase in ultraviolet radiation surely would have been seen already among all those New Yorkers who've retired and moved to Florida in recent years. Because of the higher angle of the sun, just moving from New York to Miami increases UV-B exposure by more than 200 percent!"
jsa09
not rated yet Jun 14, 2010
@ronan Yes I know There was a long term El Nino during that period and Australia was experiencing a one in a hundred year drought too. But these things are periodic and may have no relationship to Global Warming at all. Temperature fluctuates and so does rainfall with periods from a few years to a few tens of years on a regular basis. Toss in global warming and you may have minor differences but for climate change to have an effect you have to look long term.

Short term weather discrepancies do have an effect on populations in affected areas and larger weather patterns have an effect over a larger area. However these are still short term weather effects, not global warming effects.