Throughout the breeding sea son, which begins in the late winter/early spring, the boxes are checked regularly for use. This is done by the naked eye, through
binoculars, and by checking the ground beneath for signs of use (pellets, droppings, etc.). Nest boxes in use will be visited and checked at a point some time after
the babies have hatched and prior to their fledging to determine the number of successful young. Each year, the number of breeding pairs and successfully reared young will be compared to previous years numbers. Owls have traditionally been counted through broadcassing tapes of their calls to draw them down into a spotlight for individual identification. This study is projected to continue until it is determined that maximum density of avian predators has been established or a desired degree of rodent control has been achieved.