Nest boxes · Delaware

Birdhouses for Delaware

22 cavity-nesting birds breed in Delaware. The first starts nesting in January, so the box season opens in December.

Local conditions

Growing zones
USDA 7a–8a
Winter
Mild winters with modest snow; coastal marshes draw huge numbers of wintering sparrows and blackbirds.
Summer
Hot, humid summers; bay-shore woodlots are important migrant stopovers in May.
Box nesters
22 (17 year-round residents)
Hole sizes needed
16 distinct

Humid subtropical to temperate coastal plain between Delaware Bay and the Atlantic.

Box calendar for Delaware

BirdStatusHoleHeightUp byNestingClean out
Barred OwlYear-round resident7–8 in12–20 ftDecemberJanuary–MayJune
Barn OwlYear-round resident6 in10–20 ftDecemberJanuary–DecemberJanuary
Hooded MerganserYear-round resident4 × 3 in oval6–20 ftJanuaryFebruary–MayJune
Brown-headed NuthatchYear-round resident1 in5–12 ftFebruaryMarch–MayJune
Eastern Screech-OwlYear-round resident3 in10–30 ftFebruaryMarch–MayJune
American KestrelYear-round resident3 in10–30 ftFebruaryMarch–JuneJuly
Wood DuckYear-round resident4 × 3 in oval6–20 ftFebruaryMarch–JuneJuly
Brown-headed NuthatchYear-round resident1 in5–12 ftFebruaryMarch–MayJune
Eastern BluebirdYear-round resident1 1/2 in round (1 9/16 in for Mountain/Western overlap)4–6 ft on a baffled poleMarchApril–AugustSeptember
Carolina ChickadeeYear-round resident1 1/8 in round5–15 ftMarchApril–JuneJuly
Downy WoodpeckerYear-round resident1 1/4 in round5–20 ft, box packed with wood shavingsMarchApril–JuneJuly
Hairy WoodpeckerYear-round resident1 1/2 in round8–20 ft, box packed with wood shavingsMarchApril–JuneJuly
Tufted TitmouseYear-round resident1 1/4 in round5–15 ftMarchApril–JuneJuly
White-breasted NuthatchYear-round resident1 1/4 in round5–20 ftMarchApril–JuneJuly
Carolina WrenYear-round resident1 1/8–1 1/2 in5–10 ftMarchApril–AugustSeptember
Red-bellied WoodpeckerYear-round resident2 1/2 in12–20 ftMarchApril–JulyAugust
Northern FlickerYear-round resident2 1/2 in6–20 ftMarchApril–JuneJuly
Prothonotary WarblerSummer breeder1 1/8 in3–6 ft over waterMarchApril–JuneJuly
Purple MartinSummer breeder1 3/4–2 1/8 in round, or starling-resistant crescent (3 × 1 3/16 in)10–20 ft on a telescoping pole, 40+ ft from treesAprilMay–JulyAugust
House WrenSummer breeder1 to 1 1/8 in round5–10 ft near shrubsAprilMay–AugustSeptember
Tree SwallowSummer breeder1 1/2 in5–10 ftAprilMay–JuneJuly
Great Crested FlycatcherSummer breeder1 3/4 in8–20 ftAprilMay–JulyAugust

Nesting windows are shifted from each species' mid-latitude season by Delaware's latitude; year-round residents may also roost in boxes over winter, so clean them out in autumn and leave them up.

Bird guides for Delaware

Frequently asked

When should I put up a birdhouse in Delaware?

By December for the earliest local nester, the Barred Owl, which starts nesting around January.

Which birds use nest boxes in Delaware?

Barred Owl, Barn Owl, Hooded Merganser, Brown-headed Nuthatch, Eastern Screech-Owl, American Kestrel, Wood Duck, Brown-headed Nuthatch, Eastern Bluebird, Carolina Chickadee, Downy Woodpecker, Hairy Woodpecker, Tufted Titmouse, White-breasted Nuthatch, Carolina Wren, Red-bellied Woodpecker, Northern Flicker, Prothonotary Warbler, Purple Martin, House Wren, Tree Swallow, Great Crested Flycatcher.

What hole size should a Delaware birdhouse have?

It depends on the bird: the 22 local box nesters use 16 different hole sizes. See the table for each species.

Sources

  1. NestWatch nest box plans and species requirements — Cornell Lab
  2. eBird region overview and bar charts — Delaware
  3. USDA Plant Hardiness Zone Map (2023)
  4. 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.