Of 4,268 wild ducks sampled in Canada in 2005, real-time reverse transcriptase–PCR detected influenza A matrix protein (M1) gene sequence in 37% and H5 gene sequence in 5%. Mallards accounted for 61% of samples, 73% of M1-positive ducks, and 90% of H5-positive ducks. Ducks hatched in 2005 accounted for 80% of the sample.

The effective protection of coastal and estuarine habitats requires reliable monitoring information on their use by waterbirds, and the use of small unmanned aircraft systems (UAS) may provide access to these habitats without disturbing birds. We evaluated the use of a rotary-wing UAS with a high-end consumer camera to identify and count wintering waterbirds at two coastal sites in British Columbia, Canada, in January 2015, and to map mudflat and marsh habitats. Photos of shorebirds, waterfowl, and seabird species were taken at varying altitudes, and disturbance of birds appeared minimal when the UAS was flown at heights ≥61 m. A ground resolution of ~1 cm/pixel was needed to discern plumage characteristics necessary to reliably identify birds. For some duck species, identification of females relied on body size or close association with a nearby male. Photographs were also used to derive accurate counts of shorebirds. For diving birds, accurate counts from photographs will require information on the proportion of birds on the water surface. Orthomosaics of coastal habitats were constructed with sufficient detail to assess ecological and geomorphological features. The UAS can therefore assist with bird species identification, population assessment, and characterization of habitat types.

A multi-agency, Canada-wide survey of influenza A viruses circulating in wild birds, coordinated by the Canadian Cooperative Wildlife Health Centre, was begun in the summer of 2005. Cloacal swab specimens collected from young-of-year ducks were screened for the presence of influenza A nucleic acids by quantitative, real-time reverse transcription-polymerase chain reaction (RRT-PCR). Specimens that produced positive results underwent further testing for H5 and H7 gene sequences and virus isolation. In addition to live bird sampling, dead bird surveillance based on RRT-PCR was also carried out in 2006 and 2007. The prevalence of influenza A viruses varied depending on species, region of the country, and the year of sampling, but generally ranged from 20% to 50%. All HA subtypes, with the exception of H14 and H15, and all NA subtypes were identified. The three most common HA subtypes were H3, H4, and H5, while N2, N6, and N8 were the three most common NA subtypes. H4N6, H3N2, and H3N8 were the three most common HA-NA combinations. The prevalence of H5 and H7 subtype viruses appears to have a cyclical nature.

No abstract

Surveillance for avian influenza viruses in wild birds was initiated in Canada in 2005. In 2006, in order to maximize detection of highly pathogenic avian influenza viruses, the sampling protocol used in Canada's Inter-agency Wild Bird Influenza Survey was changed. Instead of collecting a single cloacal swab, as previously done in 2005, cloacal and oropharyngeal swabs were combined in a single vial at collection. In order to compare the two sampling methods, duplicate samples were collected from 798 wild dabbling ducks (tribe Anatini) in Canada between 24 July and 7 September 2006. Low pathogenic avian influenza viruses were detected significantly more often (P<0.0001) in combined oropharyngeal and cloacal samples (261/798, 33%) than in cloacal swabs alone (205/798, 26%). Compared to traditional single cloacal samples, combined samples improved virus detection at minimal additional cost.