BAITING AND BANDING: EXPERT OPINION ON HOW BAIT TRAPPING MAY INFLUENCE THE OCCURRENCE OF HIGHLY PATHOGENIC AVIAN INFLUENZA (HPAI) AMONG DABBLING DUCKS.

A Eurasian lineage highly pathogenic avian influenza virus (HPAIV) of the clade 2.3.4.4b (Goose/Guangdong lineage) was detected in migratory bird populations in North America in December 2021, and it, along with its reassortants, have since caused wild and domestic bird outbreaks across the continent. Relative to previous outbreaks, HPAIV cases among wild birds in 2022 exhibited wider geographic extent within North America and higher levels of mortality, suggesting the potential for population-level impacts. Given the possible conservation implications of HPAIV in wild birds, natural resource managers have sought guidance on actions that may mitigate negative effects of disease among North American bird populations, including modification of existing management practices. Banding of waterfowl is a critical tool for population management for several harvested species in North America, but some banding techniques, such as bait trapping, can lead to increased congregation of waterfowl, potentially altering HPAIV transmission. We used an expert opinion exercise to assess how bait trapping of dabbling ducks in Canada may influence HPAIV transmission and wild bird health. The expert group found that it is moderately likely that bait trapping of dabbling ducks in wetlands will significantly increase the transmission of HPAIV among individual ducks, but there is a low probability that this will result in significant population-level effects on North American dabbling ducks. Considering the lack of empirical work studying how capture and handling methods may change transmission of HPAIV among waterfowl, as well as the importance of bait trapping for waterfowl management in North America, future work should focus on filling knowledge gaps pertaining to the influence of baiting on HPAIV occurrence to better inform banding procedures and management decision making.

The greater snow goose Anser caerulescens atlanticus: Managing an overabundant population.

Between the early 1900s and the 1990s, the greater snow goose Anser caerulescens atlanticus population grew from 3000 individuals to more than 700 000. Because of concerns about Arctic degradation of natural habitats through overgrazing, a working group recommended the stabilization of the population. Declared overabundant in 1998, special management actions were then implemented in Canada and the United States. Meanwhile, a cost-benefit socioeconomic analysis was performed to set a target population size. Discussions aiming towards attaining a common vision were undertaken with stakeholders at multiple levels. The implemented measures have had varying success; but population size has been generally stable since 1999. To be effective and meet social acceptance, management actions must have a scientific basis, result from a consensus among stakeholders, and include an efficient monitoring programme. In this paper, historical changes in population size and management decisions along with past and current challenges encountered are discussed.