CAVITY NESTERS RECOVERY PROGRAM (CNRP) BUILD A HANGING BOX RETRIEVER

Retrieving a nest box hanging high in a tree can be challenging. Below are two simple retrievers that you can make yourself: Simple Hook Retriever and Cage Retriever.

Simple Hook Retriever ©Lee Pauser

Three parts

A 4-1/2 to 5 inch round screw hook. Preferably it is pointed on the hook end.
A paint roller. Rollers with wooden handles are preferable as they tend to be thicker, and not hollow for the entire length of the handle.
A painter's extension pole the length of which, when fully extended, will comfortably reach the highest branch from which you intend to hang a box.

Assembly

If needed, sharpen the hook's curved end to make it pointed. You should also open the hook up slightly. Both of these actions will better enable getting the hook between the tree branch and box hanger wire.
Cut the handle off the paint roller while preserving as much of the handle as possible.
Inspect the cut end of the handle. If it is hollow, you will likely need to insert a piece of a wooden dowel into the cut end of the handle to fill the empty space.
Drill a hole through the handle (and dowel) that is less in diameter than the hook's threaded end. Remember that you can always make the hole larger, but not smaller.
Fully screw the eye hook into the handle (and through the dowel) making sure it doesn't protrude on the opposite side. The hook should not be too hard or too easy to turn.
Screw the assembly onto the painter's extension pole.

Using the Hook Retriever

Usually it takes some practice to become proficient at hanging and retrieving boxes. Please practice retrieving nest boxes with an empty box before you try retrieving an occupied box. Once the box is occupied, its contents are in your hands... be careful not to drop the box.

Hanging a nest box

Select a branch that will easily support the box and provide shade for the box at least during the hottest part of the day. All day shade is naturally better. The position of the box should allow for unimpeded access.
Turn the box hanger hook such that when the box is hung, it will have the shade and access previously discussed. You may choose to reform the hook so that it better fits the branch.
Extend the retriever pole to the length needed to easily reach the branch. Securely lock the pole to prevent its length from changing during the procedure.
Slightly turn the retriever hook to the left or right so it will be pointed away from the selected branch.
While holding the retriever near the end with the hook, hang the box on the retriever hook.
Bring the pole with box into a vertical position, and moving your hands down the pole to the other end.
Lift the box hanger up and over the branch, and then lower the box.
Lift the box hanger up and over the branch, and then lower the box.

Retrieving a nest box

Observe the position of the hanging box. You want to position the retriever hook under the box hanger, but from the side of the hanger that connects directly to the box.
Turn the retriever hook slight to the left or right so it will be pointed away from the branch.
Slip the retriever hook between the box hanger and branch, lift up to free the box, and carefully lower the box.
Keep the retriever vertical for as long as you can while working your hands toward the box. The effort to support the box multiplies as the pole becomes more horizontal.
The box should remain upright due to its own weight.
When possible, grab the box hanger keeping the box upright.

Cage Retriever

This retriever is good to use if you need to capture the birds to record data. Some cage retrievers without pole attachments are available for current monitors, contact our Outreach Coordinator at outreach@scvas.org for more information.

Plans and Parts

The following plans are by Dick Purvis with notes by Chuck Wade. View these plans in PDF format.

These fit 1-inch outer-diameter PVC pipe:

Cut these lengths from a piece of pipe: two 13-inch pieces and one 12-inch piece
one tee
two right-angle connectors

Cut from 1/4-inch plywood:

2 sides: 9-1/2-inch by 7-1/2-inch
1 each front and back (add together): 9-1/2-inch 7-1/2-inch + (2x wall thickness)
1 bottom: 7-1/4-inch by 7-1/4-inch by 1/2-inch

Other parts:

two 2-1/4-inch long 5/16-18 bolts and nuts
four washers to fit the bolts
Note: Drill 3/8-inch holes in each side, centered and 1-1/2-inch from the top, to fit the bolts.
Long handle: extendable pool cleaning handle, PVC pipe, 1-1/4-inch aluminum tubing, or other