Bewick's Wren house dimensions
The Bewick's Wren nests in cup in cavities or nest boxes A box built to its measurements — and no bigger — is what makes it choose yours.
The specifications
- Entrance hole
- 1 1/4 in
- Floor (inside)
- 4 × 4 in
- Mounting height
- 5–10 ft
- Bird size
- 5.1 in, 0.3–0.4 oz
- Clutch
- 3–8 eggs
- Incubation
- 14–16 days
- Time in nest
- 14 days
- Broods
- 1–2 per season
Build and mounting checklist
- Drill the entrance to exactly 1 1/4 in — oversized holes let in European Starlings and larger predators.
- No outside perch: cavity nesters don't need one, and it helps House Sparrows and predators.
- Unpainted interior, 3/4-inch untreated wood (cedar or pine) or poly-lumber for insulation.
- Drainage holes in the floor corners and ventilation gaps under the roof.
- A side or front panel that opens so you can monitor and clean the box.
- Rough or grooved inner front wall so nestlings can climb out.
- Pole mount with a stovepipe or cone baffle to stop snakes, raccoons and cats.
When to put up a Bewick's Wren box, by state
Boxes should be up and clean a month before local nesting starts. Dates shift with latitude:
| Place | Up by | Nesting | Clean out |
|---|---|---|---|
| Arizona | January | February–June | July |
| California | January | February–June | July |
| Texas | January | February–June | July |
| Colorado | February | March–June | July |
| Nevada | February | March–June | July |
| New Mexico | February | March–June | July |
| Oklahoma | February | March–June | July |
| Oregon | February | March–June | July |
| Utah | February | March–June | July |
| Washington | February | March–June | July |
| British Columbia | March | April–June | July |
Full Bewick's Wren species guide →
Frequently asked
What size hole does a Bewick's Wren need?
1 1/4 in. A hole cut to this size admits the Bewick's Wren (5.1 in) while keeping out larger competitors.
How big should a Bewick's Wren house be inside?
A floor of 4 × 4 in. The Bewick's Wren lays 3–8 eggs, so the floor has to hold the full clutch plus growing nestlings.
How high should I mount a Bewick's Wren box?
5–10 ft. Mount on a pole with a predator baffle where possible rather than a tree or fence.
How long does a Bewick's Wren use the box?
Incubation takes 14–16 days and the young stay in the nest 14 days. Broods per year: 1–2 per season.
Sources
- Bewick's Wren — All About Birds, Cornell Lab of Ornithology
- Bewick's Wren life history — Cornell Lab of Ornithology
- Bewick's Wren — Audubon Guide to North American Birds
- NestWatch nest box plans and species requirements — Cornell Lab
Timing reflects typical patterns for the region as a whole; local dates vary with elevation and year. Check the linked eBird bar charts for your county.