When do bank swallows arrive in Colorado?
The Bank Swallow is a summer breeder in Colorado — here is when to expect it, when it leaves, and how to be ready.
Bank Swallow timing in Colorado
- Arrives
- Around April
- Leaves
- By August
- Status here
- Summer breeder
- Nesting season
- May–July
- Present roughly
- April–August
In Colorado, bank swallows are present through the warm months, arriving around April and heading south again by August.
These windows are set by latitude: Colorado sits in the middle part of this species' range, so timing here tracks the continental average closely. In any given year, weather can move the first arrivals by a week or two either way.
Month by month in this state
Highlighted months are when bank swallows are expected in Colorado. The edges of the window are the interesting weeks — first arrivals and last departures vary most from year to year.
Getting ready before they arrive
The week before April is the time to act. Have feeders cleaned, filled and out by early April — the first bank swallows into Colorado are scouting for reliable food, and a station that's ready early gets added to their route.
Once nesting begins around May, adults switch to protein-rich food for their young and visits to feeders become quick and purposeful. Expect the busiest activity at dawn.
What bank swallows eat while they're here
- Flies, mayflies, beetles and winged ants
Digs nest burrows in vertical sand banks in big colonies; needs eroding riverbanks or sand pits.
Full Bank Swallow diet guide → · Best feeder for bank swallows →
Native plants that hold bank swallows in Colorado
Food keeps a migrant for a day; habitat keeps it for the season. These Colorado-native plants are known to attract bank swallows:
Late nectar for insects and fall seed for sparrows.
Insect-rich in fall and seed in winter.
Dark summer fruit and heavy caterpillar load.
Seeds and bark insects; pygmy nuthatch and woodpecker habitat.
Acorns for jays and woodpeckers across the southern Rockies.
Late-season bloom supports insects; seed for sparrows.
Seed for crossbills, siskins and chickadees.
Early catkins draw insects for arriving warblers and hummingbirds.
Keep exploring
Frequently asked
When do bank swallows arrive in Colorado?
bank swallows typically arrive in Colorado around April, with nesting underway by May. Timing can shift a week or two with the weather in any given year.
When do bank swallows leave Colorado?
Most bank swallows have left Colorado by August. They spend the winter farther south and return the following spring.
Do bank swallows stay in Colorado all year?
No — in Colorado the Bank Swallow is a summer breeder, present roughly April–August. Outside that window it is rarely seen in the state.
What should I put out before bank swallows arrive in Colorado?
Have feeders up and clean by early April — first arrivals scout reliable food sources. Good offerings for this species: flies, mayflies, beetles and winged ants.
Sources
- Bank Swallow — All About Birds, Cornell Lab of Ornithology
- Bank Swallow life history — Cornell Lab of Ornithology
- Bank Swallow — Audubon Guide to North American Birds
- eBird region overview and bar charts — Colorado
- 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.