Eastern Bluebirds in Wisconsin
When bluebirds are present in Wisconsin, when they nest, which native Wisconsin plants feed them, and how to host them in a USDA 3b–6a yard.
- Status in Wisconsin
- Summer breeder
- Nesting window
- May–August
- Broods
- 1–3 per season
- Hardiness zones
- USDA 3b–6a
- Nest box
- 1 1/2 in round (1 9/16 in for Mountain/Western overlap) hole, 5 × 5 in floor, 4–6 ft on a baffled pole
When to expect bluebirds in Wisconsin
Eastern Bluebirds are summer residents in Wisconsin, arriving shortly before nesting begins in May and leaving after the young are independent. Through the season they feed on grasshoppers, crickets and beetles; caterpillars and spiders.
Humid continental, with two Great Lakes shorelines, northern forest and southern prairie-oak savanna.
Nesting in Wisconsin
Across Wisconsin, bluebirds typically nest from May–August. Nest site: secondary cavity nester — old woodpecker holes and nest boxes in open habitat. Females lay 2–7 eggs, incubate for 11–19 days, and young leave the nest after 15–20 days.
Warm, humid summers.
- Have boxes cleaned and mounted before April — bluebirds begin prospecting ahead of egg-laying.
- Use a 1 1/2 in round (1 9/16 in for Mountain/Western overlap) entrance on a 5 × 5 in floor, mounted 4–6 ft on a baffled pole.
- Fit a pole baffle or hole guard; ventilation gaps and drainage holes are essential.
- Clean out old nests after each brood and again after August.
Native Wisconsin plants that attract bluebirds
Of the regional native plants we track for Wisconsin, these 8 provide food or cover bluebirds use:
Dense evergreen roost cover and bluish 'berries' eaten through winter.
Early-summer berries arrive exactly when nestlings are being fed.
Deciduous holly holding red fruit into mid-winter.
Fruit clusters persist all winter as emergency food.
Red fruit heads hang on through winter.
Acorns plus hundreds of caterpillar species for nestling food.
Drought-hardy prairie oak with large acorns and a heavy insect load.
Summer fruit and one of the top caterpillar host trees.
Feeding bluebirds through the Wisconsin year
Bluebirds hunt from perches over short grass. Put mealworm feeders in the open, near a low perch, and offer small amounts at the same time each day.
- Best foods: Live or dried mealworms, Suet nuggets / insect-suet dough, Chopped native fruit.
- Avoid: Loose seed mixes — bluebirds rarely eat seed.
- In Wisconsin's summer: offer water and insect foods; natural food is abundant.
Full diet breakdown for bluebirds · Best feeder for bluebirds
Frequently asked
Are bluebirds in Wisconsin year-round?
No. Eastern Bluebirds are summer breeders in Wisconsin and leave for the winter.
When do bluebirds nest in Wisconsin?
Nesting in Wisconsin typically runs May–August, with 1–3 per season. Clutches are 2–7 eggs, incubated for 11–19 days.
What native plants attract bluebirds in Wisconsin?
Eastern red cedar, Serviceberry, Winterberry, Staghorn sumac, Smooth sumac, White oak, Bur oak, Black cherry are native plants in Wisconsin that provide food or cover for bluebirds.
What size birdhouse hole do bluebirds need?
1 1/2 in round (1 9/16 in for Mountain/Western overlap), with a floor of 5 × 5 in mounted 4–6 ft on a baffled pole.
Eastern Bluebirds in other regions
Other backyard birds in Wisconsin
Sources
- Eastern Bluebird — All About Birds, Cornell Lab of Ornithology
- Eastern Bluebird life history — Cornell Lab of Ornithology
- Eastern Bluebird — Audubon Guide to North American Birds
- NestWatch nest box plans and species requirements — Cornell Lab
- eBird region overview and bar charts — Wisconsin
- USDA Plant Hardiness Zone Map (2023)
- Audubon Native Plants Database
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.