A significant number of migrating owls passing through northern British Columbia has kept researchers at the Mugaha Marsh Banding Station extremely busy. The current owl migration is unprecedented, with a record-breaking 266 birds caught so far this season, surpassing the usual count of around 100. This surge has caused a shortage of the specialized tracking bands needed to monitor the birds, particularly in larger sizes that are essential for saw-whet owls.
The station reached out to other organizations for assistance but found that the scarcity of tracking bands was a widespread issue affecting multiple stations due to the high number of owls this year. According to Jeannine Randall, a bird biologist at the Mackenzie Nature Observatory, the surge in owl numbers is likely linked to the abundance of small rodents, which are the primary prey for these birds.
While the spike in owl numbers at the Mackenzie station is positive, it may not reflect the overall trend for owl species in the region. Rémi Torrenta, a biologist with Birds Canada, pointed out that many owl populations have been declining over the past 25 years, including the northern saw-whet owls.
Torrenta explained that the current high owl population could be part of a known four-year cycle where an abundance of owls leads to a subsequent crash in the rodent population. This phenomenon, termed a mass eruption, forces owls to migrate south in search of food. To monitor these trends, Birds Canada organizes the Nocturnal Owl Survey, a citizen science program that relies on volunteers nationwide to track owl numbers each spring.
The banding project at the Mackenzie Nature Observatory plays a crucial role in wider scientific research by providing essential data for monitoring owl populations and migration patterns. Recently, the station recaptured an owl that had been banded in Victoria in 2024, providing valuable insight into the species’ travel behavior. Jeannine Randall emphasized the importance of such research for making informed management decisions and enhancing our understanding of owl species.