West Nile Virus and Birds

A new review paper out in Bioscience documents the spread of West Nile Virus in the US–and the toll on birds. If you don’t work with birds, or the disease itself, you tend not to hear too much about the vast numbers of bird deaths.  West Nile Cycle

The media focuses mainly on human cases–but in fact, West Nile is mainly a bird disease.  Humans just get infected occasionally.

So far, over 300 species of birds have been reported killed by West Nile in the US.  From the Bioscience news release:

West Nile virus has killed hundreds of millions of birds and more than 1000 people in North America, and new outbreaks occur each year.  …Most of the bird species that suffered large population declines, such as the American crow, American robin, eastern bluebird, and tufted titmouse, have yet to recover. The extent of mortality in birds of prey and other affected animals remains largely unknown. Changes in seed dispersal, insect abundances, and scavenging services resulting from the virus’s effects on wildlife “are probable and demand attention,” according to the article’s authors, Shannon L. LaDeau, of the Smithsonian Migratory Bird Center in Washington, DC, and three others.

For a short time, the entire article is available for download free from Bioscience–it’s a nice summary of what we know about West Nile Virus and birds so far, and points out that much of “what’s next” is unknown.

That study comes out on the heels of another one in Auk, which suggests that the population crash of yellow-billed magpies on the west coast is due to West Nile (link to paper; subscription only).

So, making sure that you prevent mosquito breeding where you live not only benefits you–it saves birds!

Full Citations:
Ladeau, S.L., Marra, P.P., Kilpatrick, A.M. & Calder, C.A. (2008). West Nile Virus Revisited: Consequences for North American Ecology, BioScience, 58 (10) DOI: 10.1641/B581007
LaDeau, S.L., Kilpatrick, A.M. & Marra, P.P. (2007). West Nile virus emergence and large-scale declines of North American bird populations, Nature, 447 (7145) 713. DOI: 10.1038/nature05829
Kilpatrick, A.M., LaDeau, S.L. & Marra, P.P. (2007). ECOLOGY OF WEST NILE VIRUS TRANSMISSION AND ITS IMPACT ON BIRDS IN THE WESTERN HEMISPHERE, The Auk, 124 (4) DOI: 10.1642/0004-8038(2007)124[1121:EOWNVT]2.0.CO;2