Like most owl species, the Great Gray Owl is not well monitored in Canada, and the species' periodic irruptions in response to prey populations further complicate the situation. The best available information is from the Christmas Bird Count (CBC). CBC results, which are restricted to two regions in Alberta, suggest a large population increase relative to 1970. However, precision of the trend estimate is poor due to highly variable annual totals, and the CBC covers little of the species' range. Furthermore, CBC methods are not highly standardized and targeted efforts to record owls may have increased over time, something that could inflate trend estimates if data were sparse in the 1970s. More recently, results from the Ontario Nocturnal Owl Survey, whose methods are specifically designed to monitor owls but which covers only a small portion of the species' range in Ontario, suggest a population that has shown little overall change in Northern Ontario since 1995. Neither of these results are sufficient to establish the population status of the Great Gray Owl in Canada relative to 1970; the species is therefore considered Data Deficient. Future assessments of status will hopefully benefit from regional Nocturnal Owl Surveys once they become more widespread and amass a longer time-series. Because of the lack of information, a national population goal for the Great Gray Owl has not yet been determined.
Additional information on: Christmas Bird Count (CBC)
Additional information on: Ontario Nocturnal Owl Monitoring Program
