Saturday, April 03, 2004

New Link Added to Sidebar
The North American Bluebird Society is a non-profit conservation, education and research organization, to promote the recovery of bluebirds and other native cavity-nesting bird species.

I'm not a member - yet.

Nest Box Update
(Previous bluebird post explaining and showing a slotted nest box is here.)

West pair, front box, slotted - No activity.
West Pair, rear box, standard hole - No activity inside. Bluebird pair frequently sitting on top.

East pair, front box, slotted - No activity.
East pair, rear box, standard hole - Few blades of grass in bottom. Could be the start of a nest.

I've seen the bluebird couple sitting on a nest box every day this week. All but once they have selected the traditional box and not the safer nest box with the slot.

My former employer had nest box trails on campus. For several years I volunteered to help monitor the corporate bluebird trails. They were very successful.

Success is measured by number of fledglings of desirable species. We had bluebirds, chickadees, and swallows. Most of the young were banded by the Kalamazoo Nature Center so we could see that the birds and their offspring would come back year after year.

I learned a lot about establishing and monitoring bluebird nest boxes working in this program. And seeing the baby birds was so rewarding.

The nest boxes are erected in pairs of two with fourteen feet between the two boxes. Two bluebird couples will not nest that close to each other. It leaves a box for the other species of cavity nesting birds to nest and it provides a way to test out different types of nest boxes.

Bluebird eggs and hatchlings are prone to predation by snakes (they slither up the pole) and raccoons. Bluebird adults are subject to violent murder by English sparrows. I didn't believe this until I saw the results myself. Since then I've delighted in removing English sparrow nests from the nest boxes and smashing the eggs.

Ornithologists are always coming up with new nest box designs engineered to be safer from predators - like my two experimental slotted boxes. Unfortunately, the bluebirds always seem to prefer the traditional nest boxes and ignore the safer designs. It appears the bluebirds at Violet Acres are no exception.

Violet Acres usually has nesting tree swallows in one box, but swallows won't nest in the slotted box. If the bluebirds select the nest box with the hole, there won't be a box for the swallows.

I have a feeling I'm going to be replacing those slotted boxes with traditional boxes next spring.