Evaluation of an unmanned rotorcraft to monitor wintering waterbirds and coastal habitats in British Columbia, Canada

Abstract

The effective protection of coastal and estuarine habitats requires reliable monitoring information on their use by waterbirds, and the use of small unmanned aircraft systems (UAS) may provide access to these habitats without disturbing birds. We evaluated the use of a rotary-wing UAS with a high-end consumer camera to identify and count wintering waterbirds at two coastal sites in British Columbia, Canada, in January 2015, and to map mudflat and marsh habitats. Photos of shorebirds, waterfowl, and seabird species were taken at varying altitudes, and disturbance of birds appeared minimal when the UAS was flown at heights ≥61 m. A ground resolution of ~1 cm/pixel was needed to discern plumage characteristics necessary to reliably identify birds. For some duck species, identification of females relied on body size or close association with a nearby male. Photographs were also used to derive accurate counts of shorebirds. For diving birds, accurate counts from photographs will require information on the proportion of birds on the water surface. Orthomosaics of coastal habitats were constructed with sufficient detail to assess ecological and geomorphological features. The UAS can therefore assist with bird species identification, population assessment, and characterization of habitat types.