When February arrives, dozens of volunteers will drive to wooded areas in and around Victoria at dusk and stay out late, listening. They are part of a project launched in 2015 by the Habitat Acquisition Trust (HAT) to monitor numbers of the endangered coastal sub-species of Western Screech Owls. February to April is the birds’ breeding season and the volunteers will be listening for their distinctive courtship calls in areas where they have been known to nest in the past or have been recently reported.
Listening for owls at night is labour-intensive, but it is a labour of love for HAT volunteers and staff. In 2016, over 40 volunteers spent a total of 54 hours and travelled 60 km of survey route to discover just 4 territories where the owls were active. Last year, they got some help from technology. Automated recording units were placed at likely spots, with microphones programmed to turn on at sunset and off at midnight. The sound files they collected were analyzed by computer and helped identify two additional territories for the rare owls.
Once more commonly heard in the Greater Victoria region, Western Screech Owls numbers have fallen by over 90% in the last 10 years. There are several reasons. Habitat changes have led to an increased population of Barred Owls, which have displaced their smaller cousins. Free-roaming outdoor cats not only kill owls but their prey food of small rodents and birds. Rodenticides may also have an impact and have been found in the bodies of most owls.
In addition to its census activities, the HAT project works with landowners to encourage conservation of suitable habitats where owls can breed and find food. HAT volunteers have also begun building and installing nest boxes for owls that can be monitored in future years to gauge the success of the program. Already, two of these boxes have become home to breeding Western Screech Owl pairs, which is encouraging. In January 2018, HAT is hosting an owl monitoring training session with local Scouts, who will learn to assess nest box use at their very own Camp Barnard. Anyone wanting to become a citizen scientist — by listening for hoots, building nest boxes, or helping in other ways — is encouraged to visit hat.bc.ca for more information.
The Habitat Acquisition Trust Western Screech Owl Project is funded by the Government of Canada’s Habitat Stewardship Program and by donations from people like you. Readers are encouraged to make a donation in support of Western Screech Owl conservation at hat.bc.ca/donate or by calling 250-995-2428.
Written by HAT Volunteer, Eric Grace in collaboration with HAT Staff.