Swallows (Hirundinidae)
Baby tree swallows: from egg to fledgling
A Tree Swallow lays 4–7 eggs. They hatch after 11–20 days, and the young leave the nest 15–25 days later — about 26–45 days from egg to fledgling.
- Eggs per clutch
- 4–7 eggs
- Incubation
- 11–20 days
- Time in the nest
- 15–25 days
- Egg to fledgling
- About 26–45 days
- Broods per year
- 1 per season
- Nest
- Nest box or tree cavity lined with feathers
- Uses nest boxes
- Yes — 1 1/2 in hole
Stage by stage
- Eggs (11–20 days): 4–7 eggs per clutch. Most songbirds start incubating when the last or second-to-last egg is laid, so the young hatch close together; owls and hawks start with the first egg, so their chicks hatch days apart.
- Nestlings (15–25 days): the young hatch with little or no down and their eyes closed. They grow fast on a diet the parents bring in. In the breeding season tree swallows mainly eat flies, mayflies and dragonflies.
- Fledglings: after leaving the nest, young tree swallows are fully feathered but short-tailed and clumsy. They spend days to weeks on low branches or the ground while the parents keep feeding them.
- More broods: 1 per season.
When tree swallows nest, state by state
Nesting starts earliest in Arizona (Apr) and latest in Alaska (Jun). Months are estimates from regional breeding data shifted for latitude.
| State / province | Nesting season |
|---|---|
| Alaska | Jun–Jun |
| Alberta | Jun–Jun |
| Arizona | Apr–Jun |
| British Columbia | Jun–Jun |
| California | Apr–Jun |
| Colorado | May–Jun |
| Connecticut | May–Jun |
| Delaware | May–Jun |
| Idaho | May–Jun |
| Illinois | May–Jun |
| Indiana | May–Jun |
| Iowa | May–Jun |
| Kansas | May–Jun |
| Kentucky | May–Jun |
| Maine | Jun–Jun |
| Manitoba | Jun–Jun |
| Maryland | May–Jun |
| Massachusetts | May–Jun |
| Michigan | May–Jun |
| Minnesota | Jun–Jun |
| Missouri | May–Jun |
| Montana | Jun–Jun |
| Nebraska | May–Jun |
| Nevada | May–Jun |
| New Brunswick | Jun–Jun |
| New Hampshire | Jun–Jun |
| New Jersey | May–Jun |
| New Mexico | May–Jun |
| New York | May–Jun |
| Newfoundland and Labrador | Jun–Jun |
| North Carolina | May–Jun |
| North Dakota | Jun–Jun |
| Northwest Territories | Jun–Jun |
| Nova Scotia | Jun–Jun |
| Ohio | May–Jun |
| Oklahoma | May–Jun |
| Ontario | Jun–Jun |
| Oregon | May–Jun |
| Pennsylvania | May–Jun |
| Prince Edward Island | Jun–Jun |
| Quebec | Jun–Jun |
| Rhode Island | May–Jun |
| Saskatchewan | Jun–Jun |
| South Dakota | May–Jun |
| Tennessee | May–Jun |
| Utah | May–Jun |
| Vermont | Jun–Jun |
| Virginia | May–Jun |
| Washington | May–Jun |
| West Virginia | May–Jun |
| Wisconsin | Jun–Jun |
| Wyoming | Jun–Jun |
| Yukon | Jun–Jun |
Found a baby Tree Swallow?
- Feathered, hopping, can grip your finger: a fledgling. This is a normal stage. Keep pets and children away and watch from a distance; the parents are usually close by.
- Bare skin or only pin feathers: a nestling that fell. If you can see the nest, put it back. Touching it won't make the parents abandon it — that is a myth.
- Injured, cold, covered in flies, or caught by a cat: contact a licensed wildlife rehabilitator. In the US and Canada, ahnow.org finds the nearest one.
- Don't give water or food. Baby birds can choke, and the wrong food can kill them.
More about tree swallows
Frequently asked
How long do baby tree swallows stay in the nest?
About 15–25 days after hatching. Eggs take 11–20 days to hatch, so it is roughly 26–45 days from the last egg to the young leaving.
How many eggs does a Tree Swallow lay?
4–7 eggs per clutch, with 1 per season.
Where do tree swallows nest?
Nest box or tree cavity lined with feathers.
What should I do if I find a baby Tree Swallow on the ground?
If it has feathers and hops, it is a fledgling and its parents are almost certainly nearby — leave it. If it is naked or has pin feathers, put it back in the nest if you can. Call a licensed wildlife rehabilitator if it is injured.