I had made a couple of nest boxes for western screech owls. The first of these produced two fledglings in its second year. Here is a picture of the two, shortly after leaving the nest. A full grown western screech owl is not much bigger than these juveniles.
When cleaning out the first owl nest box around the end of October that year, the box fell apart, and a second owl box had to be made. Here is a picture of that second box, in the same location as the first, about 12 feet above the ground in a large mesquite tree.
This second owl box went up in November 2010, and had visitors over the winter and spring, but no takers in terms of nesting in spring 2011. There was considerable interest in the box by spring 2012, and I was sure a male screech owl would attract a mate to it. That might have happened, had it not been for bees moving in – in April or May of 2012.
As with the first, the second owl box was starting to crack that spring. The weight of bees and honey didn’t help, and it was in rough shape by the end of the summer. In October 2012 I had a live-bee-removal service come out and take the box and bees away one evening.
The bee man came by in an old Ford pickup truck with the driver’s side door missing, and got the now bee box down. One side of the box was split almost wide open, honeycomb filling all the gaps; the 3″ opening in the front was solid propolis, some mysterious product bees make. The bee man used a smoker with weeds as the fuel, and put in ammonium nitrate fertilizer which decomposes to nitrous oxide to keep the bees from being too agitated. Except for one bee that got in his ear, he seemed to get them all. But the next day I saw a handful of bees buzzing around the area where the bee box had been.
Oh well. Time to make a new owl box!
It was not easy to get the second bee box down, because the stainless steel screw in the mesquite tree was frozen in place. Because of this, I decided to make it so the new box could at least in theory be brought down without any tools. Also, I was motivated to make a box that would last longer than two years and to use relatively inexpensive wood.
I decided on 3.5″ X 11/16″ redwood fence wood with 5/8″ X 1 3/8″ redwood boards to bind them together . We have some adjustable clamps and exterior wood glue. Here is the basic process:
After cutting all of the pieces, it just took glue, screws, and drilling clearance and pilot holes, to make the individual boards.
There are websites devoted to such things as screech owl nest boxes, and I used the same basic design I had before. The back board is 22″, the sides and front are 16″. I glued three pieces of the fencing together, making the width of each of these boards 10.5″. I used four boards for the top so there would be overhang. The bottom piece fits inside, between the sides, so has to be cut to fit. It is better if the bottom piece is a little short. Gaps in the bottom will allow drainage should water find its way inside. Drainage holes are also drilled in the bottom for the same purpose.
I did a dry fit with the bottom, sides and front to line up those pieces before attaching them. Here are the bottom and one side:
Somewhere in here I decided to use a piece of cardboard to have an even surface to work from. Here is the bottom with both sides:
Once I had everything line up just right, I put on glue:
I quickly attached the front with four screws to locate and hold things together. This took a little doing. I predrilled the clearance holes in the front for the screws. Then I put on the glue and set the front on the sides and drilled one pilot hole in the location for one of the four screws. The pilot hole is small, 1/16″ for a #6 wood screw in soft wood. One at a time I put in the four screws shown below, realigning things before drilling each pilot hole.
After this, I quickly drilled all the pilot holes and put in all the screws before the glue set up.
After attaching the front to the sides, I attached the bottom. I had to use two-and-a-half inch screws because of the thickness of wood. I didn’t use glue.
After attaching the bottom, it was time to attach the back, the 22″ board. I lined up the sides to the back board, and put a temporary cross piece to “remember” where the bottom was when things were lined up. After doing that, I flipped over the part that was already assembled.
Then it was ready for glue and attaching the back. You can see the temporary piece that helped in lining up the back to front-side-bottom assembly.
Here is the box, almost finished, with the top set in place. Rather than have hinges for the top, I made it so the top interlocks under a cross piece attached to the back. In the front I put screw eyes and used wire to hold the top down. I made a handle out of wire to help in carrying the box.
I got wood shavings at the pet store. The owls like a few inches of shavings in the bottom of the box.
I carried the box while climbing the tree, setting it different places on the way up so I could use two hands to climb. I had made a slot in the bottom of the back board to make it easy to slip over the stainless steel screw left from the earlier owl boxes. I put a bracket on the back board to reinforce the slot.
At the top, I used wire to hold the box to a branch, and longer wire to pull the box to vertical. It is important that the box is not tilted. The owls want it to be vertical.
Here is the new box, ready for owls to find it.