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Central Valley pesticides hurt Sierra frogs
Posted: Thu Jul 23, 2009 8:28 am
by ERIC
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REMINDER: RULES FOR POSTING ON HST
Blowing in the wind: Central Valley pesticides hurt Sierra frogs
LA Times
3:55 PM, July 21, 2009
A new study adds to the evidence that Central Valley pesticide use is jeopardizing Sierra Nevada frog populations.
In laboratory experiments, Pacific treefrog and foothill yellow-legged frog tadpoles were exposed to two commonly used agricultural insecticides, chlorpyrifos and endosulfan.
Both proved toxic. Endosulfan, used on fruits and vegetables, was especially damaging to the tadpoles, which developed abnormalities and growth problems, according to a study published in the August edition of Environmental Toxicology and Chemistry.
The yellow-legged frog, whose populations are in worse shape than the tree frog, was the more sensitive of the two.
"Exposure to chlorpyrifos and endosulfan poses serious risk to amphibians in the Sierra Nevada Mountains," concluded the study authors, Donald W. Sparling of Southern Illinois University's Cooperative Wildlife Research Laboratory and Gary M. Fellers of the U.S. Geological Survey's Western Ecology Research Center in Point Reyes, Calif.
Wind blows pesticide residues from the San Joaquin Valley into the mountains, where the chemicals break down more slowly because of cooler temperatures.
Pesticides have been detected in the Sierra's air, snow and water, as well as the tissues of the range's amphibians.
-- Bettina Boxall
Photo: A yellow-legged frog. Credit: Associated Press / Vance Vredenburg, Center for Biological Diversity
Re: Central Valley pesticides hurt Sierra frogs
Posted: Thu Jul 23, 2009 6:23 pm
by rlown
Thanks for posting this, Eric. I guess this was always a theory, but i've seen no "official" scientific write-ups on proof that pesticide upslope blow-in is real (i only say this because the article was about lab tests.)
I'd love to see some real scientific field data if someone has a pointer. I'm guessing that studies of high sierra lakes includes water samples, etc that would identify toxic levels of pesticides in the frogs, water or run-off.
Re: Central Valley pesticides hurt Sierra frogs
Posted: Thu Jul 23, 2009 11:10 pm
by AldeFarte
Uh huh, sure. Please use your head when reading this item. It is an interesting tidbit Eric, but only obamer voters will swallow that sticleback. EVERYONE knows that if the "experts "could conclusively pin that one on big farming ,it would have been done by now. However , if something is repeated often enough and long enough, it will become fact. I can prove that a high enough concentration of carrot juice will cause statistical abnormalities in pollywogs. Or celery juice. Pick your poison. Sounds good in California ,though. jls
Re: Central Valley pesticides hurt Sierra frogs
Posted: Fri Jul 24, 2009 8:10 am
by dave54
Alde Farte is correct. There are many factors involved, all acting synergistically. Trying to isolate one as 'the cause' is bad science and leads to bad public policy. Unfortunately, this is the primary practice of the environmental industry and their political agenda.
Re: Central Valley pesticides hurt Sierra frogs
Posted: Fri Jul 24, 2009 6:29 pm
by rlown
i keep reading from those with Grant money to study frogs that they (amphibians) are a "bellwether" for our species. If they're (frogs) are dying off, why aren't we? Sure, eventually, everything dies out, but I'm sure i've been exposed to more harmful stuff than any Sierra frog; in a lab, or otherwise personally induced.. I'll vote for V-8 juice.. a little bit of carrot and celery in every serving..
I guess the key is Grant money.
I still can't find any documentation on Grants for this kind of research from public funds.. I'd like to though..
Russ
Re: Central Valley pesticides hurt Sierra frogs
Posted: Fri Jul 24, 2009 7:28 pm
by hikerduane
For what it's worth, I say frogs, not sure which ones, at two of the lakes I visited a couple years ago while doing the Rae Lakes Loop. One was just up from the Onion Valley TH where they had gill netted the lake.
Re: Central Valley pesticides hurt Sierra frogs
Posted: Fri Jul 24, 2009 11:43 pm
by AldeFarte
I think mylf is much more resilient than the strange people give them credit for. The ground in my neighborhood is frozen for 5 or 6 months out of every year. Every year I find small froggies in and around the garden.I live on a hillside . The only standing water is what I provide.The only fish are the 25cent goldfish I put out in the summer. Granted, they are not mylf, but they are still frogs! It is my contention that these frogs can and will find a way to make it.
Re: Central Valley pesticides hurt Sierra frogs
Posted: Tue Aug 04, 2009 2:15 pm
by norcalhiker
I'm struck by how aware hikers are about the frog decline in the sierra. Many times now people have struck up conversations about this problem with me. Too bad we're likely not going to solve it.