DDT's Resurrection
Environmental Science and Technology Online News
29 Aug 2007
N Lubick
Photo Courtesy of H Bouwman
One year after WHO recommended the use of DDT in developing countries to prevent the spread of malaria, the debate over its safety continues.
When the World Health Organization (WHO) announced last September that it supported the return of DDT in the fight against malaria, many environmentalists were taken aback. The persistent pesticide responsible for the decline of birds and other fauna in the 1950s would resuscitate what many deemed a failed approach against a disease that claims millions of lives each year. In certain settings, DDT remains a proven tool to hinder the transmission of malaria to humans, but the compound is not the long-term answer, environmentalists and public-health specialists argue.
Used as an insecticide to control malaria for the first time during World War II, DDT quickly found widespread use around the world as an agricultural spray during the "green revolution." Production hit 36,000 metric tons per year in the mid-1950s. But scientists (including Rachel Carson, author of Silent Spring, a seminal text that spurred the environmental movement in the late 1960s) began documenting some detrimental side effects: the decline of bird populations, including the bald eagle, due to the thinning of eggshells and other effects not pinned down completely until years after DDT was banned in 1972. And scientists found that some mosquitoes had become DDT-resistant, as occurs with any drug or chemical that is overused.
Rock and a Hard Place
North Coast Journal - northcoastjournal.com
30 Aug 2007
H Walters
Photo Courtesy of U.S. Fish and Wildlife Service
...“We have lethal water temperatures on the Salmon River,” said Will Harling, speaking by phone in early August from his office in Orleans. He’s the program coordinator for the Mid Klamath Watershed Council, which does restoration projects in the mid-basin to protect anadromous fisheries. “The water is 78 degrees.” Seventy-two or 73 degrees would be tolerable, he said. “But you have this warm water already, and the fish are dying of gill rot disease.” The reason this scares people is the Salmon River harbors the last continuous population of spring-run Chinook salmon in the Klamath watershed. Likely, this is because the river is undammed, less impacted than other rivers and has a number of clean cold-water creeks rushing in that create refugia for salmon during the hot summer.
Rebecca Quiñones, a biologist with the Klamath National Forest and graduate student at U.C. Davis, said there used to be spring-run Chinook throughout the Klamath River Basin. They’d come in from the ocean in May and June and hang out in the rivers and tributaries until they spawned in the fall. Dams, hydraulic mining, agriculture, logging and canneries devastated spring-run Chinook populations. Now, mostly what is left in the region are fall-run Chinook, who come into the rivers July to September. And two years ago, the spring-run Chinook population in the Salmon River took a nose dive to just less than 90 individuals. This summer, however, biologists counted about 840 individuals.
Viral Disease Killing More Hoosier Deer
South Bend Tribune - SouthBendTribune.com
31 Aug 2007
L Stout
Area: Indiana
A viral disease has been killing deer in southern Indiana, according to a Department of Natural Resources announcement last week. Hoosier hunters and landowners have reported an unusual number of dead deer in Daviess, Dubois, Gibson, Jackson, Jefferson, Perry, Pike, Spencer, Warrick, and Washington counties. DNR biologists say early tests indicate the cause is EHD (Epizootic Hemorrhagic Disease), transmitted by small flying insects called biting midges. The disease is rarely found in domestic animals and not transmissible to humans. ...
The recent EHD outbreak started earlier than the outbreak in west-central Indiana last fall when several EHD-infected deer were found in Greene, Clay, Owen, Parke, Putnam, Sullivan, Vermillion, Fountain and Vigo counties. Biologists do not expect the outbreak to cause significant deer mortality in areas where the disease hit last fall due to residual immunity in those animals.
Chronic Wasting Disease Update - Report No. 88
National Wildlife Health Center
31 Aug 2007
B Richards
Area: United States
A brief summary of current CWD events, issues, management efforts and the results of relevant scientific research.
Montana Wildlife Commissioners Set Dates, Quota for Bison Hunt
Associate Press - posted by greatfallstribune.com
30 Aug 2007
State wildlife commissioners Thursday set quotas and dates for Montana’s 2007 bison hunt, building in mechanisms to increase the number of permits if the migration out of Yellowstone National Park is conducive to a larger hunt. The action cleared the way for the Montana Department of Fish, Wildlife & Parks to release license applications this Tuesday and hold a drawing the week of Oct. 15. Last year hunters submitted about 7,000 applications for 140 state licenses, and officials expect a big demand again.
At least 44 state-issued licenses will be available for the hunt set to occur between mid-November and mid-February, the Montana Fish, Wildlife and Parks Commission decided. Commissioners recommended the two American Indian governments that participated in Thursday’s meeting set the same limit on the number of licenses they issue for tribal members seeking to hunt under treaty rights.
JOURNAL ARTICLES OF INTEREST
Chronic Wasting Disease [Review] [online abstract only]
Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease. 2007 June; 1772(6): 610-618
CJ Sigurdson et al.
Eastern Equine Encephalitis In 9 South American Camelids[online abstract only]
Journal of Veterinary Internal Medicine. 2007; 21(4): 846–852
R Nolen-Walston et al.
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