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Kingston Stovepipe Baffle The stovepipe baffle is the most effective defense against climbing predators such as raccoons, cats, rats, mice, squirrels and snakes. As raccoons are the largest ground predator likely to attack an occupied box, a baffle meant to deter squirrels is not large enough. This type of baffle should be installed before mounting the box on the pole. If the top is solid, soap should be applied inside the top and part of the way down the sides to deter wasps from building nests.
Noel Guard Constructed from 1/2" mesh hardware cloth, the Noel guard was designed to prevent raccoons and cats from reaching inside the cavity. This guard is typically used on boxes that have no other device to prevent climbing predators from reaching the box. Persistent raccoons may damage this guard, and may defeat it altogether if not securely installed.
Hutchings Predator Guard Same principle as Noel guard. Made from a 6" long section of 4" thin wall pvc and a pvc cap. Two entry holes of different diameters can be drilled in the cap for added versatility. Guard is attached to nestbox front with 3/4" wood screws. Designed by Don Hutchings. The PVC guard at left has been stained to simulate woodgrain. See how to this in our Tips and Techniques section.
Conical (Zeleny) Baffle Conical baffles made of sheet metal will help deter squirrels, raccoons, cats and snakes. This type of baffle is useful if boxes are mounted on wooden posts and can be installed after a box is mounted. Raccoons may eventually learn their way around a conical baffle. Sharp edges require caution.
Huber Sparrow Trap Installed on plywood panel which is then installed in nestbox as shown. To set, metal plate is swiveled up and held in place with arming rod. As bird enters the nestbox it trips the arm, releasing the metal plate to pivot down over the entry.
Gilbertson Universal Sparrow Trap Installed inside box just below entry. Metal band made from piece of retractable tape measure is bent down to engage wire retaining arm. When bird enters nestbox it trips arm, releasing the band which closes over the entry hole. Trap works on both wood and pvc boxes. Download plan: 230kb (pdf)
Sparrow Spooker It's not clear why House Sparrows in particular fear the reflective ribbons of the sparrow spooker, but most do, so this device has a fairly good success rate at deterring them. Spookers are easy to make with PVC pipe or dowels and streamers made of mylar, ribbon or strips from a potato chip bag.
Spookers are installed after the first egg is laid and removed immediately after the nestlings fledge. This schedule is important to prevent sparrows from becoming accustomed to the device.
Download plan: 145 kb (pdf)