Colorado · Summer breeder

Bullock's Orioles in Colorado

When Bullock's orioles are present in Colorado, when they nest, which native Colorado plants feed them, and how to host them in a USDA 3a–7b yard.

Blackbirds (Icteridae)Bullock's OrioleIcterus bullockii
Status in Colorado
Summer breeder
Nesting window
May–July
Broods
1 per season
Hardiness zones
USDA 3a–7b

When to expect Bullock's orioles in Colorado

Bullock's Orioles are summer residents in Colorado, arriving shortly before nesting begins in May and leaving after the young are independent. Through the season they feed on caterpillars.

Semi-arid high plains in the east and the Rocky Mountains through the center, with most backyards between 5,000 and 7,000 ft.

Nesting in Colorado

Across Colorado, Bullock's orioles typically nest from May–July. Nest site: hanging woven pouch. Females lay 4–5 eggs, incubate for 11–14 days, and young leave the nest after 12–14 days.

Warm, dry days and cool nights; afternoon storms are common in July and August.

  • Bullock's Orioles don't use nest boxes. Keep dense native shrubs and trees such as smooth sumac, virginia creeper, pin cherry for nest sites.
  • Delay heavy pruning of shrubs until after July.

Native Colorado plants that attract Bullock's orioles

Of the regional native plants we track for Colorado, these 8 provide food or cover Bullock's orioles use:

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.

Cardinal flower
Lobelia cardinalis · Perennial

Scarlet late-summer spikes; a hummingbird magnet in moist soil.

Wild bergamot
Monarda fistulosa · Perennial

Tubular flowers for hummingbirds and seed heads for finches.

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.

Feeding Bullock's orioles through the Colorado year

Weaves hanging nests in cottonwoods along western rivers.

  • Best foods: Oranges, Grape jelly, Nectar.
  • In Colorado's summer: offer water and insect foods; natural food is abundant.

Full diet breakdown for Bullock's orioles · Best feeder for Bullock's orioles

Frequently asked

Are Bullock's orioles in Colorado year-round?

No. Bullock's Orioles are summer breeders in Colorado and leave for the winter.

When do Bullock's orioles nest in Colorado?

Nesting in Colorado typically runs May–July, with 1 per season. Clutches are 4–5 eggs, incubated for 11–14 days.

What native plants attract Bullock's orioles in Colorado?

Smooth sumac, Virginia creeper, Cardinal flower, Wild bergamot, Pin cherry, Chokecherry, Red-osier dogwood, Rocky Mountain juniper are native plants in Colorado that provide food or cover for Bullock's orioles.

Bullock's Orioles in other regions

Other backyard birds in Colorado

Sources

  1. Bullock's Oriole — All About Birds, Cornell Lab of Ornithology
  2. Bullock's Oriole life history — Cornell Lab of Ornithology
  3. Bullock's Oriole — Audubon Guide to North American Birds
  4. eBird region overview and bar charts — Colorado
  5. USDA Plant Hardiness Zone Map (2023)
  6. 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.