How long until the eggs hatch, and when will the young leave? This page puts the nesting numbers for 15 common backyard nesters side by side, from the Nesting Facts on each species' life-history page in the Cornell Lab's All About Birds and from NestWatch's table of averages, then turns them into dates for a nest you are watching. Box sizes are in birdhouse dimensions; what to do once the young have gone is in when to clean out birdhouses.
Quick read
Eggs: virtually all songbirds lay one egg a day, usually early in the morning, until the clutch is complete (All About Birds).
Incubation: usually starts after the last or second-to-last egg (NestWatch), then runs about 12–17 days in the NestWatch averages below.
Nestlings: 10–21 days in the nest in the NestWatch averages; a typical successful songbird nest lasts about 30 days from start to finish (NestWatch).
The nesting timeline table
Each cell gives Cornell's range first, then NestWatch's average in parentheses. NestWatch says its averages are based on Birds of the World and Baicich and Harrison's Nests, Eggs, and Nestlings of North American Birds. "Nestling" is the time from hatching to leaving the nest; "broods" is Cornell's number of broods a pair raises per season.
Open-cup nesters
| Species | Clutch (eggs) | Incubation (days) | Nestling (days) | Broods |
|---|---|---|---|---|
| Northern Cardinal | 2–5 (4) | 11–13 (12) | 7–13 (10) | 1–2 |
| American Robin | 3–5 (4) | 12–14 (13) | 13 (15) | 1–3 |
| Mourning Dove | 2 (2) | 14 (15) | 12–15 (14) | 1–6 |
| House Finch | 2–6 (4–5) | 13–14 (13) | 12–19 (15) | 1–6 |
| American Goldfinch | 2–7 (5) | 12–14 (13) | 11–17 (14) | 1–2 |
| Blue Jay | 2–7 (4–5) | 17–18 (17) | 17–21 (19) | 1 |
| Ruby-throated Hummingbird | 1–3 (2) | 12–14 (16) | 18–22 (19) | 1–2 |
Cavity and nest-box nesters
| Species | Clutch (eggs) | Incubation (days) | Nestling (days) | Broods |
|---|---|---|---|---|
| Black-capped Chickadee | 1–13 (6–8) | 12–13 (13) | 12–16 (14) | 1 |
| Tufted Titmouse | 3–9 (5–6) | 12–14 (13) | 15–16 (17) | 1 |
| White-breasted Nuthatch | 5–9 (—) | 13–14 (—) | 26 (—) | 1 |
| House Wren | 3–10 (6–8) | 9–16 (14) | 15–17 (15) | 1–2 |
| Carolina Wren | 3–7 (4–6) | 12–16 (13) | 10–16 (13) | 1–3 |
| Eastern Bluebird | 2–7 (4–5) | 11–19 (14) | 17–21 (17) | 1–3 |
| Tree Swallow | 4–7 (4–6) | 11–20 (15) | 15–25 (20) | 1–2 |
| Downy Woodpecker | 3–8 (4–5) | 12 (12) | 18–21 (21) | 1 |
— = not in NestWatch's table, which lists no nuthatch. Broods are Cornell's figures; NestWatch's table has no brood column.
Mourning Doves and House Finches can raise up to six broods in a season, while Blue Jays, chickadees, titmice, nuthatches and Downy Woodpeckers raise one (Cornell). Late starters exist too: American Goldfinch pairs "do not nest until mid-summer," when thistles and other weeds have gone to seed (Cornell).
Where the numbers disagree
| Species | Cornell (All About Birds) | NestWatch average | Other source |
|---|---|---|---|
| Ruby-throated Hummingbird incubation | 12–14 days | 16 days, outside Cornell's range | — |
| American Robin nestling period | 13 days | 15 days | — |
| Mourning Dove incubation | 14 days | 15 days | — |
| Tufted Titmouse nestling period | 15–16 days | 17 days | — |
| Black-capped Chickadee clutch | 1–13 eggs | 6–8 eggs | — |
| Eastern Bluebird incubation | 11–19 days | 14 days in the table; 11–19 days on NestWatch's bluebird page | Virginia DCR monitoring guide: 12–14 days |
| Eastern Bluebird time in the nest | 17–21 days | 17 days in the table; a 17–19 day "brooding period" on its bluebird page | Virginia DCR: fledge 18–21 days after hatching |
Cornell's columns are ranges that include the extremes; NestWatch's are averages. Use the averages to plan and the ranges as outer limits before deciding a nest has failed.
How a nest cycle adds up
Count the days from the first egg:
- Laying. At one egg a day, the last egg comes about (eggs − 1) days after the first. All About Birds says some larger species lay only every 2–3 days, so for them it takes longer.
- Incubation. It usually starts after the last or second-to-last egg (NestWatch), so hatching is about the last-egg date plus the incubation period, or a day earlier. In bluebird boxes, Virginia DCR's guide says all the chicks hatch on the same day.
- Nestlings. Fledging is about the hatch date plus the nestling period.
Worked example (Eastern Bluebird, NestWatch averages): 5 eggs, first egg on day 0. The last egg comes on day 4; with 14 days of incubation the eggs hatch about day 18; after 17 days as nestlings the young leave about day 35.
Found a nest with eggs already in it? NestWatch backdates the first egg at one egg per day. Its example: 2 eggs on May 10 and 4 eggs on May 13 means the eggs were laid May 9, 10, 11 and 12, so the first egg date is May 9.
- Northern Cardinal: 4 eggs, 12 days of incubation, 10 days as nestlings: about 25 days from first egg to fledging.
- American Robin: 4 eggs, 13 and 15 days: about 31 days.
- Mourning Dove: 2 eggs, 15 and 14 days: about 30 days.
- American Goldfinch: 5 eggs, 13 and 14 days: about 31 days.
- Ruby-throated Hummingbird: 2 eggs, 16 and 19 days: about 36 days.
- Eastern Bluebird: 4 eggs, 14 and 17 days: about 34 days.
- Downy Woodpecker: 4 eggs, 12 and 21 days: about 36 days.
- 30 days: NestWatch's length of a typical successful songbird nest.
Nest date estimator
Pick the species, enter the date of the first egg (backdate it as above if needed) and the number of eggs once laying has stopped. The estimator uses the formula above with NestWatch's averages, and shows Cornell's ranges as the earliest and latest likely dates. For a species not listed, choose "Other" and enter the days yourself. Nothing you enter leaves your browser.
The estimator's species values are the NestWatch averages and Cornell ranges in the tables above; White-breasted Nuthatch is left out because NestWatch gives no average for it.
When to check a nest, and when to stay away
These steps follow NestWatch's Code of Conduct for nest monitors.
- Check every 3–4 days. Weekly checks still give useful data; a typical 30-day songbird nest needs about 5–10 visits.
- Go in late morning or afternoon. Not early morning, when most birds lay and adults that leave can let eggs or young chill; not at or after dusk; not in cold, damp or rainy weather.
- Stay under one minute. Have your notes ready before you go, and write them once you are well away.
- Skip the first few days of incubation. Watch from a distance and go in only when the female is off the nest.
- Give the parent a chance to leave. At a nest box, tap the box, then tap again once it is open. Never force a sitting bird off; come back later.
- Stop close to fledging. Disturbance can make young leave early, and early fledglings have low survival. Once they are fully feathered and alert, watch only from a distance. For bluebird boxes, TWRA says not to open the box from 12 days after hatching; Virginia DCR's guide says day 12 in its schedule and day 13 in its count guide.
- Leave no trail. Do not handle eggs or young, watch for cats, crows and jays following you, and leave by a different route than you came.
Federal law covers the nest too. The U.S. Fish and Wildlife Service says it is illegal to collect or possess migratory bird nests, and that destroying a nest in a way that takes birds or their eggs is illegal; it calls a nest inactive when it "contains no eggs or chicks and is no longer being used by birds for breeding." The nest-cleaning guide covers the details, and a young bird on the ground is covered in found a baby bird.
Nest-watch checklist
- Species identified and its row found in the table
- First-egg date recorded or backdated at one egg per day
- Hatch and fledge dates estimated, with Cornell's range as the outer limit
- Visits every 3–4 days, late morning or afternoon, under a minute each
- No visits in the first days of incubation or once the young are fully feathered
- Bluebird box: no opening from 12 days after hatching
- Box cleaned only when the nest is inactive
For your Bird-a-Day streak
The table tells you roughly how many days a nest you know about will stay active. Log the species in the streak tracker. NestWatch collects nest records from volunteers, and its Code of Conduct above is written for them.
Sources
- All About Birds, Cornell Lab of Ornithology, Nesting Facts on the life-history pages for Northern Cardinal, American Robin, Mourning Dove, House Finch, American Goldfinch, Blue Jay, Ruby-throated Hummingbird, Black-capped Chickadee, Tufted Titmouse, White-breasted Nuthatch, House Wren, Carolina Wren, Eastern Bluebird, Tree Swallow and Downy Woodpecker
- How Many Eggs Does a Bird Lay? — All About Birds, Cornell Lab
- Clutch Size & Phenology for Common Species — NestWatch, Cornell Lab
- How do I estimate first egg, hatch, and fledge dates? — NestWatch FAQ
- Code of Conduct — NestWatch
- Eastern Bluebird — NestWatch focal species
- Eastern Bluebird Nest Box — Tennessee Wildlife Resources Agency (TWRA)
- Bluebird monitoring guide (PDF) — Virginia Department of Conservation and Recreation, State Parks
- Bird nests — U.S. Fish and Wildlife Service