Mounting Boxes on Poles: Our System for Security

There are several good techniques for mounting boxes on poles.
On this page we’ll show you our nest box mounting method.
We like it because it holds boxes securely to poles and prevents them from slipping down.
This method also allows us to remove boxes easily after nesting for cleaning, disinfecting with bleach, making repairs, and off-season storage.

2 pipe hanger straps (below left), the two hole kind. Make sure to use only the size that fits tightly on your poles.
1 small hose clamp (below right).
4 sets machine screws and nuts, plus two washers per set.
We use 8-32 x 1-1/4″ screws with matching nuts and washers.

At home drill holes for machine screws in back of box, aligning them so the pipe straps will attach as in the picture below.
Make the holes the same size as the screws so the boxes won’t be loose.

Insert screws from the inside of the box only, using one washer with each.
Add pipe straps, second washers, and nuts.
We do the above two steps at home, leaving the spaces between straps and boxes open enough so boxes can be slipped easily onto poles in the field.

It’s often easiest to slide the pole through the straps, then tighten the screws most, but not all the way, before setting the pole in a hole in the ground.

Once a box is positioned on a pole at the desired height and direction the straps can be tightened down securely. We use a short screwdriver and a small wrench for this.

To prevent boxes from slipping down poles we attach a hose clamp under each box (see below), positioned so the box rests atop the clamp’s screw.
We use a screwdriver or wrench to tighten the clamp as firmly as possible.

Mounting boxes on poles is best done before the swallows begin to return, but not absolutely necessary.
Tree Swallows return earlier than most spring migrant songbirds. Exactly when differs by region. Ask local birders for their expected arrival time in your area.
Digging may be hard or impossible in the wet or frozen ground of early spring, so you may be forced to wait until conditions improve.
The shortage of nest cavities usually means some swallows will still be looking for nesting places weeks after most have arrived. The male swallow below was still searching in mid May and claimed this box as soon as it was erected.
However, your chances for 100% occupancy are better if your boxes are up early.

Five and one-half to six feet from ground to entrance hole is a good height. You want to make it hard for predators to jump to boxes.
Don’t mount boxes any lower even if it means you’ll need to step up on something to check box contents. (We bring a dry-wall bucket with us for use as a combination stool, seat, and gear carrier).
It seldom takes floating Tree Swallows, those without boxes, long to find new ones.

Experiments mounting boxes on poles have shown that early in the Tree Swallow nesting season boxes facing south, southeast or east are preferred, perhaps because these boxes are apt to warm up faster and more thoroughly in the morning.
In the second half of the season direction does not seem to effect box choice.
Caution: If there’s a strong prevailing wind at your project site consider facing your boxes away from it, regardless of direction.

These bars aren’t necessary but, if present, are favorite perches for the swallows.
They are easily constructed from two pieces of 1/2″ wooden dowel.
The lower end is wrapped with duct tape and then twisted by hand into the top opening of the metal pole.
The duct tape will wad up in the pole, holding the perch-bar in place.
Another option is to fasten perch bars directly to boxes.

Two pairs of Tree Swallows will not nest side by side in two boxes mounted on one pole.
However, Tree Swallows, will nest surprisingly close to some other species.
For example, swallows and bluebirds will sometimes nest in boxes attached to the same pole, and box pairing is a tactic to consider if swallow-bluebird competition for single boxes is a troublesome issue for you. (See Reducing Competition Between Bluebirds and Tree Swallows).

It is also common to see swallow boxes attached to the backs of Wood Duck boxes, in order to reduce Tree Swallow annoyance of the ducks.
Over the years Steve Simmons of California has had 12 different species combinations in boxes paired on single poles, including the Barn Owls and Tree Swallows in his photo below.

So boxes intended for different species, mounted on one pole, may be appropriate in some circumstances if it reduces interspecific competition or saves money.
But be aware that not all species coexist well. (See House Sparrow Damage to Tree Swallow Nestings and Reducing House Wren Damage to Tree Swallow Nestings).

Next Step: Tree Swallow Nest Box Grids

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