Tree Swallows in New Jersey
When tree swallows are present in New Jersey, when they nest, which native New Jersey plants feed them, and how to host them in a USDA 6a–7b yard.
- Status in New Jersey
- Summer breeder
- Nesting window
- May–June
- Broods
- 1 per season
- Hardiness zones
- USDA 6a–7b
- Nest box
- 1 1/2 in hole, 5 × 5 in floor, 5–10 ft
When to expect tree swallows in New Jersey
Tree Swallows are summer residents in New Jersey, arriving shortly before nesting begins in May and leaving after the young are independent. Through the season they feed on flies, mayflies and dragonflies.
Humid continental to subtropical, from the Highlands in the north to the Pine Barrens and Cape May.
Nesting in New Jersey
Across New Jersey, tree swallows typically nest from May–June. Nest site: nest box or tree cavity lined with feathers. Females lay 4–7 eggs, incubate for 11–20 days, and young leave the nest after 15–25 days.
Hot, humid summers; Cape May is a world-class migration funnel.
- Have boxes cleaned and mounted before April — tree swallows begin prospecting ahead of egg-laying.
- Use a 1 1/2 in entrance on a 5 × 5 in floor, mounted 5–10 ft.
- Fit a pole baffle or hole guard; ventilation gaps and drainage holes are essential.
- Clean out old nests after each brood and again after June.
Native New Jersey plants that attract tree swallows
Of the regional native plants we track for New Jersey, these 8 provide food or cover tree swallows use:
Fat-rich red fall fruit taken by thrushes, bluebirds and woodpeckers.
Early-summer berries arrive exactly when nestlings are being fed.
Acorns plus hundreds of caterpillar species for nestling food.
Summer fruit and one of the top caterpillar host trees.
Late-summer berry clusters taken by over 40 bird species.
Blue-black fall fruit and dense nesting cover.
Lipid-rich red fruit fuels fall migrants.
Late nectar for insects and fall seed for sparrows.
Feeding tree swallows through the New Jersey year
Tree swallows readily take bluebird-style nest boxes; mount boxes in pairs 15–25 ft apart to share with bluebirds.
- Best foods: Crushed eggshells in spring.
- In New Jersey's summer: offer water and insect foods; natural food is abundant.
Full diet breakdown for tree swallows · Best feeder for tree swallows
Frequently asked
Are tree swallows in New Jersey year-round?
No. Tree Swallows are summer breeders in New Jersey and leave for the winter.
When do tree swallows nest in New Jersey?
Nesting in New Jersey typically runs May–June, with 1 per season. Clutches are 4–7 eggs, incubated for 11–20 days.
What native plants attract tree swallows in New Jersey?
Flowering dogwood, Serviceberry, White oak, Black cherry, American elderberry, Arrowwood viburnum, Spicebush, New England aster are native plants in New Jersey that provide food or cover for tree swallows.
What size birdhouse hole do tree swallows need?
1 1/2 in, with a floor of 5 × 5 in mounted 5–10 ft.
Tree Swallows in other regions
Other backyard birds in New Jersey
Sources
- Tree Swallow — All About Birds, Cornell Lab of Ornithology
- Tree Swallow life history — Cornell Lab of Ornithology
- Tree Swallow — Audubon Guide to North American Birds
- NestWatch nest box plans and species requirements — Cornell Lab
- eBird region overview and bar charts — New Jersey
- 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.