Migratory Birds: Innocent Scapegoats for the Dispersal of the H5N1 Virus
Blackwell Publishing Ltd. (Posted by eurekalert.org)
26 Mar 2007
A review to be published shortly in the British Ornithologists' Union's journal, Ibis, critically examines the arguments concerning the role of migratory birds in the global dispersal of the highly pathogenic avian influenza virus H5N1. Ecologists of the Station Biologique de la Tour du Valat and of the GEMI-CNRS in the Camargue (France), Michel Gauthier-Clerc, Camille Lebarbenchon and Frédéric Thomas conclude that human commercial activities, particularly those associated with poultry, are the major factors that have determined its global dispersal. Highly pathogenic avian influenza virus subtype H5N1 was first detected in poultry in November 1996 in south-east China. The virus subsequently dispersed throughout most of Asia, and also to Africa and Europe.
From mid-2005, migratory wild birds have been widely considered to be the primary source of the dispersal of H5N1 outside Asia. This claim was based on the discovery in May 2005 that hundreds of wild birds had died on Lake Quinghaihu, on the high Asian plateau in China. It is however clear that the trajectory of the virus does not correspond with to the main migration routes of wild birds. The global network of migration routes seemed to hide the globalisation - without strict health control - of the exchanges of poultry, the more likely mechanism for disease spread.
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>>>Recent Expansion of Highly Pathogenic Avian Influenza H5N1: A Critical Review
Physorg.com
27 Mar 2007
Area: Austin, Texas USA
Female rats avoid males whose great-grandfathers were exposed to a common fruit crop fungicide, preferring instead males whose ancestors were uncontaminated, researchers from The University of Texas at Austin have discovered. Their research shows that environmental contamination could affect the evolution of wildlife through changes in mating behavior. Drs. David Crews and Andrea Gore examined mate preference in male and female rats whose great-grandparents were exposed to the fungicide vinclozolin, which causes early onset of cancer and kidney disease in males. They found that female rats could tell the difference between male descendants of rats that had or had not been exposed to vinclozolin.
The females strongly preferred to associate with males descended from unexposed rats. Their research will be published the week of March 26-30 in the online Early Edition of the Proceedings of the National Academy of Sciences. “Even across generations, your attractiveness as a mate is decreased if your great-grandfather has been exposed to environmental chemicals,” said Gore, professor of pharmacology and toxicology in the College of Pharmacy. “That will have an impact on your ability to reproduce and could take you out of the gene pool.”
California Sea Otters' Comeback Faces Hurdles from Man, Nature
The Mercury News
26 Mar 2007
S Bohan
Area: California USA
State Bill Aims to Protect and Fund Stalled Recovery
The lone man strolling on top of the stone breakwater at Pillar Point harbor in Princeton by the Sea last week had no idea he was witnessing natural history in the making. Below him, in waters reflecting the gray of an overcast afternoon sky, a California sea otter floated on its back, its head and tail protruding above the water. The man strolled past the gently bobbing animal. But from a slender aluminum motor boat a hundred yards a way, Jack Ames, a marine biologist with the California Department of Fish and Game who has studied sea otters for more than three decades, knew the animal was worth his heed.
Minutes before, where the harbor opens to the Pacific Ocean, Ames and two other marine biologists on board saw five other otters, floating on their backs in a rough circle. Upon seeing them, Ames shouted out, "There are sea otters!" and the other two spun around to see the animals. The otters at Pillar Point keep hopes alive that the imperiled population, listed as threatened under the federal Endangered Species Act, may resume its stalled recovery. The playful animals once ranged along inland coastal waters from Baja to Washington, in numbers approaching 20,000, researchers estimate.
Lake Near Power Plant Closed to AnglersPrinceton Daily Clarion
27 Mar 2007
M Crowley
Photo courtesy of Duke Energy
Area: Princeton, Indiana USA
The 3,000-acre Gibson Lake at the Gibson Generating Station, west of Princeton, will not reopen to the public for fishing this year, Duke Energy officials announced Monday. The lake, which traditionally opens April 1, will remain closed to due high levels of selenium found in its water. But the property's outer ponds and sloughs will remain open, as no selenium was found in these bodies of water. Selenium is a naturally occurring trace element found in most rocks and soil, and is bio-cumulative, which means it builds up in the biological system of a fish, as bigger fish eat smaller fish.
Some species of fish are affected more than others by selenium. Some such as bluegill can tolerate only minute levels, while species such as catfish can endure much higher levels. High levels of selenium have been known to disrupt the reproductive cycles and cause deformities in juvenile and adult fish, birds and other egg-laying wildlife. Duke Energy Indiana will be working with state and federal resource agencies, as well as independent experts, to study any potential ecological impacts.
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>>>State Officials to Discuss Limiting Fish Consumption at Horsetooth Reservoir
New Exhibit on Infectious Diseases Opens March 31 at the Koshland Science Museum in Washington , D.C.
National Academy of Sciences (Posted by infectioncontroltoday.com)
26 Mar 2007
Area: Washington, D.C. USA
The threat of infectious disease can be felt in all corners of the globe, from the rapid spread of HIV/AIDS, to the search for vaccines that can protect against new strains of the flu. Infectious disease is a global burden, affecting policy decisions and personal health choices around the world. On March 31, the MarianKoshlandScienceMuseum will open a new interactive exhibit, Infectious Disease: Evolving Challenges to Human Health. This exhibit provides an in-depth view of the microbes that cause some of the world's most deadly diseases and explores the challenges facing researchers today.
"New threats emerge every day because of microbial evolution, more rapidly changing environments, and the increased movement of people over short and long distances," said Elliott Kieff, chairman of the scientific steering committee that oversaw the creation of the exhibit, and professor of medicine and microbiology and molecular genetics at HarvardUniversity. "Our response to microbes determines the spread of disease." This major exhibit features interactive displays providing a rarely seen view of our microbial world. Visitors will gain an understanding of how scientists develop tools and strategies to treat diseases.
Recent Expansion of Highly Pathogenic Avian Influenza H5N1: A Critical Review [online abstract only]
IBIS. 2007 Mar 20; [epub ahead of print]
M Gauthier-Clerc
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