California · Year-round resident

Brown-headed Cowbirds in California

When cowbirds are present in California, when they nest, which native California plants feed them, and how to host them in a USDA 5a–11a yard.

Blackbirds (Icteridae)Brown-headed CowbirdMolothrus ater

Status in California: Year-round resident
Nesting window: March–July
Broods: —
Hardiness zones: USDA 5a–11a

When to expect cowbirds in California

Brown-headed Cowbirds live in California all year. Wet, mild winters are the green season — the busiest time at coastal feeders as sparrows and hummingbirds settle in. That makes the cold months the time your yard matters most to them.

Mediterranean along the coast and Central Valley, alpine in the Sierra Nevada, and desert in the southeast.

Nesting in California

Across California, cowbirds typically nest from March–July. Plan around that window: February for setup, July for clean-out.

Dry summers with little rain from May to October; water and summer-blooming natives matter more than extra seed.

Brown-headed Cowbirds don't use nest boxes. Keep dense native shrubs and trees such as rabbitbrush, palo verde, prickly pear for nest sites.
Delay heavy pruning of shrubs until after July.

Native California plants that attract cowbirds

Of the regional native plants we track for California, these 8 provide food or cover cowbirds use:

Wild bergamot

Monarda fistulosa · Perennial

Tubular flowers for hummingbirds and seed heads for finches.

Black-eyed Susan

Rudbeckia hirta · Perennial

Prolific seed heads for finches and sparrows.

Common sunflower

Helianthus annuus · Perennial

Annual native sunflower — the original feeder seed.

Little bluestem

Schizachyrium scoparium · Perennial

Native bunchgrass; winter seed and ground cover for sparrows and juncos.

Tall goldenrod

Solidago altissima · Perennial

Insect-rich in fall and seed in winter.

Rabbitbrush

Ericameria nauseosa · Shrub

Late-season bloom supports insects; seed for sparrows.

Palo verde

Parkinsonia florida · Tree

Seed pods and insect-rich spring bloom.

Prickly pear

Opuntia engelmannii · Shrub

Fruit and seed plus nest sites for Cactus Wrens.

Feeding cowbirds through the California year

Top foods: Millet, Cracked corn.
In California's winter: Wet, mild winters are the green season — the busiest time at coastal feeders as sparrows and hummingbirds settle in.

Full diet breakdown for cowbirds · Best feeder for cowbirds

Frequently asked

Are cowbirds in California year-round?

Yes. Brown-headed Cowbirds are year-round residents in California.

When do cowbirds nest in California?

Nesting in California typically runs March–July, with —. Clutches are up to 36 eggs per season, one per host nest, incubated for 10–12 days.

What native plants attract cowbirds in California?

Wild bergamot, Black-eyed Susan, Common sunflower, Little bluestem, Tall goldenrod, Rabbitbrush, Palo verde, Prickly pear are native plants in California that provide food or cover for cowbirds.

Other backyard birds in California

Purple Martin Downy Woodpecker Hairy Woodpecker American Goldfinch White-breasted Nuthatch House Wren House Finch Purple Finch Mourning Dove American Robin Dark-eyed Junco Song Sparrow Chipping Sparrow Northern Flicker Pileated Woodpecker Red-breasted Nuthatch Brown Creeper Red-winged Blackbird Pine Siskin Northern Mockingbird Cedar Waxwing Tree Swallow Barn Swallow Yellow-rumped Warbler House Sparrow European Starling Steller's Jay California Scrub-Jay Mountain Chickadee Chestnut-backed Chickadee Bushtit Oak Titmouse Juniper Titmouse Pygmy Nuthatch Anna's Hummingbird Black-chinned Hummingbird Costa's Hummingbird Lesser Goldfinch Cassin's Finch California Towhee Spotted Towhee Gambel's Quail California Quail Western Bluebird Mountain Bluebird Say's Phoebe Black Phoebe Acorn Woodpecker Gila Woodpecker Ladder-backed Woodpecker Nuttall's Woodpecker Cactus Wren Verdin Bewick's Wren White-crowned Sparrow Golden-crowned Sparrow Fox Sparrow Varied Thrush Violet-green Swallow Black-headed Grosbeak Lazuli Bunting Bullock's Oriole Eurasian Collared-Dove White-winged Dove American Crow Common Raven Cooper's Hawk Sharp-shinned Hawk Red-tailed Hawk Great Horned Owl American Kestrel Wood Duck Wild Turkey Mallard Great Blue Heron Belted Kingfisher Ruby-crowned Kinglet Golden-crowned Kinglet Hermit Thrush Winter Wren Pine Grosbeak Red Crossbill Western Tanager Hooded Oriole Phainopepla Black-throated Sparrow Lark Sparrow Green-tailed Towhee California Thrasher Clark's Nutcracker Yellow-billed Magpie Western Screech-Owl Hooded Merganser Band-tailed Pigeon Yellow Warbler Common Yellowthroat Yellow-breasted Chat Orange-crowned Warbler Warbling Vireo Western Kingbird Vermilion Flycatcher Ash-throated Flycatcher Cliff Swallow Northern Rough-winged Swallow Bank Swallow Common Nighthawk Canada Goose American Coot Killdeer Spotted Sandpiper Green Heron Great Egret Black-crowned Night Heron Turkey Vulture Osprey Bald Eagle Red-shouldered Hawk Merlin Peregrine Falcon Northern Saw-whet Owl Barn Owl Burrowing Owl Lewis's Woodpecker Black-backed Woodpecker White-headed Woodpecker Savannah Sparrow Vesper Sparrow Lapland Longspur Horned Lark Blue Grosbeak Cactus Wren Greater Roadrunner Yellow-billed Cuckoo Yellow-headed Blackbird Brewer's Blackbird Great-tailed Grackle Rock Pigeon

Sources

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.