AN OPTIC DEVICE TO INSPECT NEST BOXES FROM THE GROUND

Nest boxes used to manage and study some species of owls, American kes trel (Falco sparverius), and flying squirrels (Glaucomys sabrinus) are most effective when hung high on the boles of trees. Monitoring these boxes by tree climbing is time consuming, may damage the trees, and p resents a safety risk. An optic device was developed to peer into larg e nest boxes hung up to 10.5 m above the ground. The device (nest box checker) consists of a periscope-like head with light source, which is raised to the nest box on a 10.5-m telescoping pole. Unused boxes cou ld be distinguished from boxes with lichen, owls or residual nesting m aterial by viewing the box interior using binoculars. Monitoring boxes with this device took less (xBAR = 6.4 +/- 1.04 min, range 2.7-13.5) time than climbing to inspect each box (xBAR = 7.5 +/- 0.98 min, range 2.8-15.0).