Below is the abstract from an article in today's issue of the journal Nature. Most readers will remember the arrival of the mosquito-borne West Nile virus eight years ago in the US (a gift from Uganda, apparently), and predictions of its effects on our birds. The Washington Post has an article treating this study of Breeding Bird Survey data on 20 representative North American species, intended to measure the possible effect of this virus on populations of common birds. Here are some highlights. Thirteen of the 20 species seemed unaffected, but over the period since the virus arrived, Carolina chickadees were down 68% in Maryland and 50% in Virginia from projected levels. American crows have lost up to 45% of their numbers in some areas, 100% in others. Eastern bluebirds are down by 44%. Maryland robins suffered a 32% loss. Titmice took a big hit. House wrens and blue jays, however, seem to have recovered their lost numbers. BBS numbers are of course limited; they are less reliable in assessing numbers of waterfowl, nocturnal migrants, and raptors,for example. My own subjective impressions over this eight years generally match these results in Ohio: chickadees and titmice seem down; crows seem down; wrens and jays were down, but seem to have rebounded. I haven't noticed an impact on robin numbers, and I am just not familiar enough with bluebird populations to say one way or another; no doubt others are. The Nature article also discusses the ill effects that changes in certain bird populations may have on the larger ecosystem. If you don't subscribe to Nature, a good library will. This is all part of the Floridization of our part of the world, resulting from introduced pathogens, exotic species, and other pests. There seems to be very little we can easily do about it. Bill Whan "Nature advance online publication 16 May 2007 doi:10.1038/nature05829; Received 8 November 2006; Accepted 11 April 2007; Published online 16 May 2007 "Nature advance online publication 16 May 2007 | doi:10.1038/nature05829; Received 8 November 2006; Accepted 11 April 2007; Published online 16 May 2007 West Nile virus emergence and large-scale declines of North American bird populations Shannon L. LaDeau, A. Marm Kilpatrick & Peter P. Marra1 1. Smithsonian Migratory Bird Center, National Zoological Park, Washington DC 20008, USA 2. Consortium for Conservation Medicine, New York, New York 10001, USA Correspondence to: Shannon L. LaDeau1 Correspondence and requests for materials should be addressed to S.L.L. (Email: [log in to unmask]). Top of page Emerging infectious diseases present a formidable challenge to the conservation of native species in the twenty-first century. Diseases caused by introduced pathogens have had large impacts on species abundances, including the American chestnut, Hawaiian bird species and many amphibians. Changes in host population sizes can lead to marked shifts in community composition and ecosystem functioning. However, identifying the impacts of an introduced disease and distinguishing it from other forces that influence population dynamics (for example, climate) is challenging and requires abundance data that extend before and after the introduction. Here we use 26 yr of Breeding Bird Survey (BBS)8 data to determine the impact of West Nile virus (WNV) on 20 potential avian hosts across North America. We demonstrate significant changes in population trajectories for seven species from four families that concur with a priori predictions and the spatio-temporal intensity of pathogen transmission. The American crow population declined by up to 45% since WNV arrival, and only two of the seven species with documented impact recovered to pre-WNV levels by 2005. Our findings demonstrate the potential impacts of an invasive species on a diverse faunal assemblage across broad geographical scales, and underscore the complexity of subsequent community response." ______________________________________________________________________ Ohio-birds mailing list, a service of the Ohio Ornithological Society. Our thanks to Miami University for hosting this mailing list. Additional discussions can be found in our forums, at www.ohiobirds.org/forum/. You can join or leave the list, or change your options, at: http://listserv.muohio.edu/scripts/wa.exe?LIST=OHIO-BIRDS Send questions or comments about the list to: [log in to unmask]