Eco-Ping!
Posted on 08/11/2005 9:07:52 AM PDT by GreenFreeper
Roundup Kills Frogs as well as Tadpoles, Pitt Biologist Finds
PITTSBURGH — As amphibians continue to mysteriously disappear worldwide, a University of Pittsburgh researcher may have found more pieces of the puzzle. Elaborating on his previous research, University of Pittsburgh assistant professor of biological sciences Rick Relyea has discovered that Roundup, the most commonly used herbicide in the world, is deadly to tadpoles at lower concentrations than previously tested, that the presence of soil does not mitigate the chemical’s effects, and that the product kills frogs in addition to tadpoles.
In two articles published in the August 1 issue of the journal Ecological Applications, Relyea and his doctoral students Nancy Schoeppner and Jason Hoverman found that even when applied at concentrations that are one-third of the maximum concentrations expected in nature, Roundup® still killed up to 71 percent of tadpoles raised in outdoor tanks.
Relyea also examined whether adding soil to the tanks would absorb the Roundup® and make it less deadly to tadpoles. The soil made no difference: After exposure to the maximum concentration expected in nature, nearly all of the tadpoles from three species died.
Although Roundup® is not approved for use in water, scientists have found that the herbicide can wind up in small wetlands where tadpoles live due to inadvertent spraying during the application of Roundup®.
Studying how Roundup® affected frogs after metamorphosis, Relyea found that the recommended application of Roundup® Weed and Grass Killer, a formulation marketed to homeowners and gardeners, killed up to 86 percent of terrestrial frogs after only one day.
"The most striking result from the experiments was that a chemical designed to kill plants killed 98 percent of all tadpoles within three weeks and 79 percent of all frogs within one day," Relyea wrote.
Previous studies have determined that it is Roundup®’s surfactant (polyethoxylated tallowamine, or POEA, an "inert" ingredient added to make the herbicide penetrate plant leaves) and not the active herbicide (glyphosate) that is lethal to amphibians.
This research was funded by the National Science Foundation, Pitt’s McKinley Fund, and the Pennsylvania Academy of Science.
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Complete Citation
THE LETHAL IMPACT OF ROUNDUP ON AQUATIC AND TERRESTRIAL AMPHIBIANS Ecological Applications 15(4): 1118-1124 Rick A. Relyea Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
Abstract. The global decline in amphibian diversity has become an international environmental problem with a multitude of possible causes. There is evidence that pesticides may play a role, yet few pesticides have been tested on amphibians. For example, Roundup is a globally common herbicide that is conventionally thought to be nonlethal to amphibians. However, Roundup has been tested on few amphibian species, with existing tests conducted mostly under laboratory conditions and on larval amphibians. Recent laboratory studies have indicated that Roundup may be highly lethal to North American tadpoles, but we needed to determine whether this effect occurs under more natural conditions and in post-metamorphic amphibians. I assembled communities of three species of North American tadpoles in outdoor pond mesocosms that contained different types of soil (which can absorb the pesticide) and applied Roundup as a direct overspray. After three weeks, Roundup killed 96–100% of larval amphibians (regardless of soil presence). I then exposed three species of juvenile (post-metamorphic) anurans to a direct overspray of Roundup in laboratory containers. After one day, Roundup killed 68–86% of juvenile amphibians. These results suggest that Roundup, a compound designed to kill plants, can cause extremely high rates of mortality to amphibians that could lead to population declines.
Species used: Bufo maericanus, Hyla versicolor, Rana pipiens
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A gratis downloadable pdf of this and other current papers by Relyea is available from the CNAH PDF Library on the CNAH web site home page at:
http://www.cnah.org/cnah_pdf.asp
Roundup is poison. How can poison kill frogs?
"The Center for North American Herpetology"
Why do they care about frogs when they're supposed to be studying herpes?
The frogs probably absorb it through their skin.
I don't use anything on my lawn and I'm over run with grass frogs. Ive never seen so many of the bug eaters.
Eco-Ping!
I have a lot of frogs on my farm until the tenant sprays his roundup ready corn................
> Roundup is poison. How can poison kill frogs?
"Previous studies have determined that it is Roundup®’s
surfactant (polyethoxylated tallowamine, or POEA, an
"inert" ingredient added to make the herbicide penetrate
plant leaves) and not the active herbicide (glyphosate)
that is lethal to amphibians."
Sounds like it's not the active ingredient that's the
problem, and a reformulation might fix it.
We need to evolve a roundup-proof frog.
why? Is there skin like a paper towel? Maybe frogs are like super absorbant tampons. I don't really know.
Basically a fancy soap. Other soaps will probably have the same problem.
Previous studies have determined that it is Roundup®’s surfactant (polyethoxylated tallowamine, or POEA, an "inert" ingredient added to make the herbicide penetrate plant leaves) and not the active herbicide (glyphosate) that is lethal to amphibians.
Interesting..................It appears to be the surfactant, NOT the roundup itself.
> We need to evolve a roundup-proof frog.
Since it doesn't kill all of them, that process is
by definition already in progress.
The propert term is a "Round-up Ready" frog...
A friend from Dupont once told me that you could drink Roundup without ill effect. There were no frogs present, or he might have been less confident.
But they would just surrender first...oh wait you mean those frogs, nevermind.
Perhaps, but it's the surfactant that is causing the problems. Roundup or any other herbicide isn't of much use if the chemical rolls of the vegetation. The semi-permeable skin of amphibians is likely to be sensitive to any surfactant regardless of a reformulation.
Maybe it kills what they eat and they die from lack of food?
Since it doesn't kill all of them, that process is by definition already in progress.
Wrong, we need God to wave his magic wand and MAKE such a frog...
Sarcasm, yes.
It doesn't take a frog a day to starve to death.
This is quite disappointing, it sounds very lethal. Probably has the same effect on other amphibians as well.
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