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
God doesn't need to interfere at this point as he has already included the needed gene into the frogs DNA.
The last sentance was a joke, BTW, as I am not a christian and do not subscribe to ID or creationism and I do not subscribe to evolution either.
If you are going to talk about species surviving attacks of this kind please stick to facts and don't try to make out as if survival of the fittest is evolution.
It has been proven not to be, by evolutionists, hence neo-darwinism with mutation thrown in. I will not go into that and leave it to you to flame me all you want. Don't count on me reading it however, because you will not use facts and simply call me names and I can do without name calling. Thanks.
The cause of the high Roundup-associated mortality appears to result from direct toxicity (possibly due to damaged epithelial cells in the gills; Edginton et al. 2004) rather than any indirect effect of Roundup-in-duced reduction of algal food resources in the meso-cosms and subsequent tadpole starvation. Three pieces of evidence support this conclusion. First, I observed numerous dead tadpoles within the first 24 hours, which would not be expected if the cause of death were star-vation (Audo et al. 1995; the exact amount of death could not be quantified without destructively sampling the mesocosms). Second, in a separate mesocosm ex-periment, Roundup actually increased, rather than de-creased, periphyton biomass because there were so few tadpoles to consume the algae (Relyea 2005a). Third, in a laboratory study in which six species of North isopropylamine salt (the latter two formulations of gly-phosate lack the POEA surfactant). Perkins et al. (2000) American tadpoles were fed ground fish flakes, Round-up still caused rapid death at 1 to 5 mg AI/L (Relyea 2005b).
Doesn't the new Round-Up carry a surfactant that wasn't in the original version? Knock off 41% glyphosate is available in Oregon for around $50 a gallon and less for 2 1/2 gallons....
The last few years at the shooting club I belong to, I have seen frogs everywhere. Toads on the sporting clays trails, leopard frogs jumping through the grass on the archery and skeet range, bullfrogs and greenfrogs and misc. tadpoles in the pound and along the incoming and outgoing brooks. Ain't no shortage of the little buggers!
I don't know. Monsanto is very tight lipped about the surfactant system, but I have read that it is POEA (polyethoxylated tallowamine).
Glyphosphate has been found to induce a mutiple sclerosis-like condition in humans, so who knows what it might do to frogs.
That line caused me to start singing the old hymn that said "Yield not to temptation, for yielding is sin..." It save me from blurting out another off-color comment right here in the middle of a beautiful natural thread on anphibians in God's green earth!!!
See! He's not finished with me yet!!!
IOW, look out for the crooks!
Jumping into your argument would be akin to jumping overboard on a submarine.
My grandmother's oldest daughter used to make pickled beans and soap. her basement was a maze of crocks with the bathroom open to all who were successful in the negotiation.
When I'm upset, my son-in-law's wife is usually the cause (I love her dearly).
We are completely surrounded here by crops of Roundup-Ready beans and we have had more frogs and toads in the last few years than I can remember. So this does not wash with me.
We are completely surrounded here by crops of Roundup-Ready beans and we have had more frogs and toads in the last few years than I can remember. So this does not wash with me.
The worst kind.
Sounds nasty. Was that digestion or emulsion?
It was a miasmic fantasy, all cloaky and gloom.
A poisonous atmosphere formerly thought to rise from swamps and putrid matter and cause disease.
Reminiscent cause for a blue dart festival.
I have an in-law from Alabama (now a Baptist minister) who burned all the hair off his arms and eyebrows in just such an exposition.
I guess he was just flaming gaily.
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