Satellite-marked waterfowl reveal migratory connection between H5N1 outbreak areas in China and Mongolia DIANN J. PROSSER, 1 * JOHN Y. TAKEKAWA, 2 SCOTT H. NEWMAN, 3 BAOPING YAN, 4 DAVID C. DOUGLAS, 5 YUANSHENG HOU, 6 ZHI XING, 6 DEHAI ZHANG, 6 TIANXIAN LI, 7 * YONGDONG LI, 7 DELONG ZHAO, 8 WILLIAM M. PERRY 2 & ERIC C. PALM 2 1 United States Geological Survey, Patuxent Wildlife Research Center, Beltsville, MD 20705 USA and University of Maryland, College Park, MD 20742 USA 2 United States Geological Survey, Western Ecological Research Center, Vallejo, CA 94592 USA 3 EMPRES Wildlife Unit, Animal Health Service, Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, Rome, Italy 00153 4 Chinese Academy of Sciences, Computer Network Information Center, Beijing, China 100080 5 United States Geological Survey, Alaska Science Center, Juneau, AK 99801 USA 6 Qinghai Lake National Nature Reserve, Xining, China 810003 7 Chinese Academy of Sciences, State Key Laboratory of Virology, Wuhan Institute of Virology, Hubei, China 430071 8 Chinese Academy of Sciences, Institute of Zoology, Beijing, China 100101 The role of wild birds in the spread of highly pathogenic avian influenza H5N1 has been greatly debated and remains an unresolved question. However, analyses to determine involvement of wild birds have been hindered by the lack of basic information on their movements in central Asia. Thus, we initiated a programme to document migrations of waterfowl in Asian flyways to inform hypotheses of H5N1 transmission. As part of this work, we studied migration of waterfowl from Qinghai Lake, China, site of the 2005 H5N1 outbreak in wild birds. We examined the null hypothesis that no direct migratory connection existed between Qinghai Lake and H5N1 outbreak areas in central Mongolia, as suggested by some H5N1 phylogeny studies. We captured individuals in 2007 from two of the species that died in the Qinghai Lake outbreaks and marked them with GPS satellite transmitters: Bar-headed Geese Anser indicus (n = 14) and Ruddy Shelduck Tad- orna ferruginea (n = 11). Three of 25 marked birds (one Goose and two Shelducks) migrated to breeding grounds near H5N1 outbreak areas in Mongolia. Our results describe a previously unknown migratory link between the two regions and offer new critical information on migratory movements in the region. Keywords: highly pathogenic avian influenza H5N1, satellite telemetry, waterfowl, wild birds. Highly pathogenic avian influenza (HPAI) H5N1 virus (hereafter H5N1) continues to threaten soci- eties worldwide with the potential for a human pandemic. The precursor to the currently circulat- ing H5N1 was first discovered in an outbreak in domestic geese in southeastern China in 1996 (Guo et al. 1998, Xu et al. 1999, Zhao et al. 2008). In 1997, the reassorted virus emerged in poultry and humans in Hong Kong, causing the first documented human fatalities from a purely avian influenza virus (Claas et al. 1998). H5N1 has since continued to circulate in poultry in Asia under multiple re-emergence events (Guan et al. 2002, Li et al. 2004, Sims et al. 2005, Chen et al. 2006a, Sims & Brown 2008, Wang et al. 2008). However, in April 2005 more than 6000 wild birds, including 3282 Bar-headed Geese Anser indi- cus and 145 Ruddy Shelducks Tadorna ferruginea, died of H5N1 infection on nesting grounds at Qinghai Lake, north-central China (Chen et al. 2005, 2006b, Liu et al. 2005). This outbreak *Corresponding authors. Email: dprosser@usgs.gov; litx@wh.iov.cn Journal compilation ª 2009 British Ornithologists’ Union No claim to original US government works Ibis (2009), 151, 568–576