Chimney Swifts in Iowa
When chimney swifts are present in Iowa, when they nest, which native Iowa plants feed them, and how to host them in a USDA 4b–6a yard.
- Status in Iowa
- Summer breeder
- Nesting window
- May–July
- Broods
- 1 per season
- Hardiness zones
- USDA 4b–6a
When to expect chimney swifts in Iowa
Chimney Swifts are summer residents in Iowa, arriving shortly before nesting begins in May and leaving after the young are independent. Through the season they feed on flies, beetles, ants and aphids in flight.
Humid continental prairie state, with loess hills in the west and the Driftless Area in the northeast.
Nesting in Iowa
Across Iowa, chimney swifts typically nest from May–July. Nest site: half-cup of twigs glued with saliva inside chimneys. Females lay 4–5 eggs, incubate for 16–21 days, and young leave the nest after 28–30 days.
Hot, humid summers with thunderstorms.
- Chimney Swifts don't use nest boxes. Keep dense native shrubs and trees such as serviceberry, white oak, bur oak for nest sites.
- Delay heavy pruning of shrubs until after July.
Native Iowa plants that attract chimney swifts
Of the regional native plants we track for Iowa, these 8 provide food or cover chimney swifts use:
Early-summer berries arrive exactly when nestlings are being fed.
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.
Late-summer berry clusters taken by over 40 bird species.
Lipid-rich red fruit fuels fall migrants.
Late nectar for insects and fall seed for sparrows.
Insect-rich in fall and seed in winter.
Feeding chimney swifts through the Iowa year
Leave an uncapped masonry chimney open April–October, or build a swift tower; populations have fallen by roughly two-thirds since 1966.
- Best foods: .
- In Iowa's summer: offer water and insect foods; natural food is abundant.
Frequently asked
Are chimney swifts in Iowa year-round?
No. Chimney Swifts are summer breeders in Iowa and leave for the winter.
When do chimney swifts nest in Iowa?
Nesting in Iowa typically runs May–July, with 1 per season. Clutches are 4–5 eggs, incubated for 16–21 days.
What native plants attract chimney swifts in Iowa?
Serviceberry, White oak, Bur oak, Black cherry, American elderberry, Spicebush, New England aster, Tall goldenrod are native plants in Iowa that provide food or cover for chimney swifts.
Chimney Swifts in other regions
Other backyard birds in Iowa
Sources
- Chimney Swift — All About Birds, Cornell Lab of Ornithology
- Chimney Swift life history — Cornell Lab of Ornithology
- Chimney Swift — Audubon Guide to North American Birds
- eBird region overview and bar charts — Iowa
- 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.