Migration timing

When do ash-throated flycatchers arrive in Colorado?

The Ash-throated Flycatcher is a summer breeder in Colorado — here is when to expect it, when it leaves, and how to be ready.

Ash-throated Flycatcher, verified photograph
Photo: Wikimedia Commons

Ash-throated Flycatcher timing in Colorado

Arrives
Around March
Leaves
By August
Status here
Summer breeder
Nesting season
April–July
Present roughly
March–August

In Colorado, ash-throated flycatchers are present through the warm months, arriving around March 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

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Highlighted months are when ash-throated flycatchers 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 March is the time to act. Have feeders cleaned, filled and out by early March — the first ash-throated flycatchers into Colorado are scouting for reliable food, and a station that's ready early gets added to their route.

Ash-throated flycatchers nest in cavities, so boxes need to be up and cleaned before arrival — a box mounted after they've claimed territories will usually sit empty until next year. Ash-throated Flycatcher nest box dimensions and mounting →

Once nesting begins around April, adults switch to protein-rich food for their young and visits to feeders become quick and purposeful. Expect the busiest activity at dawn.

What ash-throated flycatchers eat while they're here

  • Grasshoppers, wasps, caterpillars and spiders

Uses nest boxes, pipes and even mailboxes across the dry West; rarely needs to drink.

Full Ash-throated Flycatcher diet guide → · Best feeder for ash-throated flycatchers →

Native plants that hold ash-throated flycatchers in Colorado

Food keeps a migrant for a day; habitat keeps it for the season. These Colorado-native plants are known to attract ash-throated flycatchers:

Smooth sumac
Rhus glabra · Shrub

Red fruit heads hang on through winter.

Virginia creeper
Parthenocissus quinquefolia · Vine

Blue fruit on red stems in early fall.

New England aster
Symphyotrichum novae-angliae · Perennial

Late nectar for insects and fall seed for sparrows.

Tall goldenrod
Solidago altissima · Perennial

Insect-rich in fall and seed in winter.

Pin cherry
Prunus pensylvanica · Tree

Fast-growing northern cherry with midsummer fruit.

Chokecherry
Prunus virginiana · Shrub

Dark summer fruit and heavy caterpillar load.

Red-osier dogwood
Cornus sericea · Shrub

White fruit and red winter stems; good thicket cover.

Rocky Mountain juniper
Juniperus scopulorum · Tree

Berry-like cones feed bluebirds, solitaires and waxwings in winter.

Keep exploring

Frequently asked

When do ash-throated flycatchers arrive in Colorado?

ash-throated flycatchers typically arrive in Colorado around March, with nesting underway by April. Timing can shift a week or two with the weather in any given year.

When do ash-throated flycatchers leave Colorado?

Most ash-throated flycatchers have left Colorado by August. They spend the winter farther south and return the following spring.

Do ash-throated flycatchers stay in Colorado all year?

No — in Colorado the Ash-throated Flycatcher is a summer breeder, present roughly March–August. Outside that window it is rarely seen in the state.

What should I put out before ash-throated flycatchers arrive in Colorado?

Have feeders up and clean by early March — first arrivals scout reliable food sources. Good offerings for this species: grasshoppers, wasps, caterpillars and spiders.

Sources

  1. Ash-throated Flycatcher — All About Birds, Cornell Lab of Ornithology
  2. Ash-throated Flycatcher life history — Cornell Lab of Ornithology
  3. Ash-throated Flycatcher — Audubon Guide to North American Birds
  4. NestWatch nest box plans and species requirements — Cornell Lab
  5. eBird region overview and bar charts — Colorado
  6. USDA Plant Hardiness Zone Map (2023)
  7. 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.