| correlations of daily activity with avian cholera mortality among wildfowl. | we tested the hypothesis that wildfowl activities can influence the risk of avian cholera (pasteurella multocida infection) for susceptible birds at centerville, humboldt county, california (usa). avian cholera mortality characteristics from past epizootics were correlated with variations in flock size, habitat use and 11 feeding and nonfeeding behaviors among six empirically defined groups of wildfowl: american coots (fulica americana), tundra swans (cygnus columbianus), american wigeon (anas a ... | 1991 | 1758019 |
| cross-seasonal patterns of avian influenza virus in breeding and wintering migratory birds: a flyway perspective. | abstract the spread of avian influenza viruses (aiv) in nature is intrinsically linked with the movements of wild birds. wild birds are the reservoirs for the virus and their migration may facilitate the circulation of aiv between breeding and wintering areas. this cycle of dispersal has become widely accepted; however, there are few aiv studies that present cross-seasonal information. a flyway perspective is critical for understanding how wild birds contribute to the persistence of aiv over l ... | 2011 | 21995264 |
| epizootiological features of avian cholera on the north coast of california. | an avian cholera (pasteurella multocida) epizootic was observed among wildfowl at the centerville gun club, humboldt county, california (usa) in january 1978. compared to their live populations and use of the area, coots (fulica americana) died in proportionately greater numbers than any other species. coots collected by gunshot were evaluated for sex and age composition, and morphometry from november 1977 through mid-january 1978 at this site. there was no substantial difference in the sex, age ... | 1989 | 2716104 |
| organic and total mercury in muscle tissue of five aquatic birds with different feeding habits from the se gulf of california, mexico. | we measured organic and total hg in muscle tissue of five species of aquatic birds from the south-eastern gulf of california region, mexico. concentrations of total and organic hg measured in pelecanus occidentalis were the highest (2.85 and 2.68 microgg(-1)); lowest values of organic hg (0.20 microgg(-1)) and total hg (0.47 microgg(-1)) were detected in anas discors and anas clypeata, respectively. differences of hg levels were related to feeding habits, being concentrations in birds of piscivo ... | 2009 | 19419748 |
| influenza a viruses in wild birds of the pacific flyway, 2005-2008. | avian influenza viruses (aivs) pose a significant threat to public health, and viral subtypes circulating in natural avian reservoirs can contribute to the emergence of pathogenic influenza viruses in humans. we investigated the prevalence and distribution of aivs in 8826 migratory and resident wild birds in north america along the pacific flyway, which is a major north-south migration pathway that overlaps with four other flyways in alaska providing opportunities for mixing of eurasian and amer ... | 2010 | 20059316 |
| genetic structure of pacific flyway avian influenza viruses is shaped by geographic location, host species, and sampling period. | the eight gene segments of avian influenza virus (aiv) reassort frequently and rapidly to generate novel genotypes and subtypes that are transmissible to a broad range of hosts. there is evidence that aiv can have a restricted host range and can segregate in space and time. host-virus relationships at the species, geographic, and spatial scales have not been fully defined for aiv populations of the pacific flyway, particularly among the diverse waterfowl that occupy the flyway in alaska and cali ... | 2012 | 22222690 |
| waterfowl ecology and avian influenza in california: do host traits inform us about viral occurrence? | we examined whether host traits influenced the occurrence of avian influenza virus (aiv) in anatidae (ducks, geese, swans) at wintering sites in california's central valley. in total, 3487 individuals were sampled at sacramento national wildlife refuge and conaway ranch duck club during the hunting season of 2007-08. of the 19 anatidae species sampled, prevalence was highest in the northern shoveler (5.09%), followed by the ring-necked duck (2.63%), american wigeon (2.57%), bufflehead (2.50%), g ... | 2010 | 20521673 |