Quick Answer
Barn Owl nest boxes should be placed at a minimum height of 10-15 feet above the ground. The ideal height range is 12-18 feet high in open habitats like fields or pastures. In wooded areas, boxes can be placed a bit lower at 10-12 feet high. Placing the box high enough deters predators and provides the owls a sense of security.
Height Recommendations
Here are some general height recommendations for installing a Barn Owl nest box:
- Open habitats (fields, meadows, pastures): 12-18 feet high
- Along tree lines and woodland edges: 10-15 feet high
- Wooded areas: 10-12 feet high
Placing the box at least 10-12 feet high is a good minimum to follow. Barn Owls prefer nesting high up with a clear flight path in and out of the box entrance. Nest boxes placed too low are more prone to disturbance and predation.
Why Height Matters
The height of the nest box affects:
- Safety from predators – Higher boxes keep eggs and young owlets safer from climbing predators like raccoons, foxes, and cats.
- Takeoff and landing – Barn Owls need a clear vertical flight path straight down from the nest when leaving and approaching with food.
- Temperature regulation – Higher boxes are better ventilated and less prone to overheating in hot summer months.
- Feeling of security – Barn Owls feel more secure and undisturbed when nesting high up.
Barn Owl legs and feet are not adapted for grasping. They need a clear vertical drop off the nest to take flight. Lower boxes can impede their landing and takeoff. Higher boxes essentially provide better “runway access” for Barn Owls coming and going from the nest.
Typical Barn Owl Nesting Sites
When nesting in natural sites, Barn Owls are most commonly found in these high up locations:
- Cavities and crevices in trees
- Old stick nests of other birds
- Haylofts and upper rafters of barns and sheds
- Church steeples, clock towers, and abandoned buildings
- Caves and cliff cavities
Mimicking these types of high nest sites with properly positioned nest boxes makes them more attractive and usable for breeding Barn Owls.
Choosing the Right Height
Here are some tips for choosing the optimal height for your Barn Owl box:
- In open areas, err on the higher end of the height range (15-18 ft).
- In wooded areas, boxes can be on the lower end (10-12 ft).
- Measure the height to the base of the box, not the entry hole.
- Use a sturdy mounting pole that won’t sway in winds.
- Have a clear flight path free of branches and obstructions.
- Aim for the highest stable mounting height available.
If mounting on a building or tree, be sure to situate the box above the highest vertical jump reach of predators. Cats, raccoons, and certain snake species can sometimes jump and climb 5-6 feet vertically onto flat surfaces. Position the box out of their maximum vertical reach.
It’s also a good idea to install predator guards or baffles on the mounting pole if feasible. This further prevents climbing predators from accessing the box.
Ideal Pole Type by Location
The nest box mounting pole needs to be strong and stable at the height required. Here are some pole recommendations by habitat:
Open Habitats
- 10-20 ft metal poles or treated 4×4-inch wood posts strongly anchored into the ground.
Woodland Edges
- Mount lower on tree trunks (10-15 ft) on a wooden platform.
- Use 16-20 ft treated 4×4-inch wood posts or metal poles along the forest edge.
Woodlands
- Mount on tree trunks 10-12 ft up.
In open areas, it’s best to provide a dedicated mounting pole for the box since high branches strong enough to hold the box are scarce. In wooded areas, mounting on tree trunks typically provides the easiest high installation.
Pole and Mounting Considerations
Here are some other tips for selecting and installing nest box mounting poles:
- Dig pole foundations 2-3 feet deep into the ground and set in concrete for maximum stability.
- Use wood corner bracing or guy wires to add support if needed.
- Allow pole tops to extend at least 2-3 feet above the box for owls to perch.
- Include predator baffles on wooden poles to prevent climbing.
- Use metal poles or add saucepans inverted over wooden poles to prevent climbing.
- Have a level box to prevent eggs from rolling out.
Proper pole selection, bracing, and baffles can help make your Barn Owl nest box installation a long-lasting success. Added stability keeps the box in prime nesting position for many years.
Conclusion
For Barn Owls, nest box height matters. Follow these best practice recommendations:
- Minimum height of 10-15 feet.
- Ideal height of 12-18 feet.
- Higher end of range for open areas.
- Lower end of range for wooded areas.
- Sturdy pole that won’t sway in wind.
- Clear and obstacle-free flight path to box.
Aim for the highest stable mounting height that works for your site and habitat. Barn Owls will appreciate a box placed up high, allowing them to nest safely with a clear way in and out.