A significant number of migrating owls have kept the Mugaha Marsh Banding Station in northern British Columbia extremely busy this year. Jeannine Randall, a bird biologist at the Mackenzie Nature Observatory, located approximately 200 kilometers north of Prince George, expressed excitement about the exceptional owl activity. The usual capture count of around 100 owls has skyrocketed to 266 this season, setting a new record with two weeks remaining. However, this surge has posed a challenge due to a shortage of specialized tracking bands needed to monitor the birds, particularly the larger sizes required for saw-whet owls.
Facing a band shortage, the station sought assistance from other organizations but found that the issue was widespread among various stations experiencing similar scarcities. Randall attributed the spike in owl numbers to an abundance of small rodents, the primary prey of these birds. She noted that most captured owls were young birds hatched this year, suggesting a correlation between the owl population increase and the availability of prey such as mice and voles.
Although the high owl numbers in Mackenzie are promising, Rémi Torrenta from Birds Canada mentioned a concerning trend of declining owl populations over the past 25 years in the province. While some owl species like barred owls are stable or increasing, many others, including northern saw-whet owls, are on a decline. Torrenta explained that the current owl boom is likely part of a known four-year cycle where an overabundance of owls leads to a subsequent crash in the rodent population, forcing the owls to migrate south in search of food, known as a mass eruption.
To gain insights into these trends, Birds Canada coordinates the Nocturnal Owl Survey, a citizen science initiative engaging volunteers nationwide to monitor owl populations each spring. This collaborative effort helps track owl numbers and behaviors, providing valuable data for conservation efforts and understanding owl migration patterns. The banding project at the Mackenzie Nature Observatory plays a crucial role in contributing to broader scientific research on owl populations and migration routes.
In a recent development, the station recaptured an owl originally banded in Victoria in 2024, shedding light on the species’ movements. Randall emphasized the importance of such research in informing management decisions and enhancing species knowledge.