Ontario · Year-round resident

Brown-headed Cowbirds in Ontario

When cowbirds are present in Ontario, when they nest, which native Ontario plants feed them, and how to host them in a Canadian zones 0a–7a yard.

Blackbirds (Icteridae)Brown-headed CowbirdMolothrus ater

Status in Ontario: Year-round resident
Nesting window: May–July
Broods: —
Hardiness zones: Canadian zones 0a–7a (southern Ontario roughly equivalent to USDA 4–6)

When to expect cowbirds in Ontario

Brown-headed Cowbirds live in Ontario all year. Cold, snowy winters; feeder flocks are dominated by chickadees, nuthatches, woodpeckers and finches. That makes the cold months the time your yard matters most to them.

Humid continental in the south, boreal and subarctic in the north; most backyard birding happens in the southern Great Lakes lowlands.

Nesting in Ontario

Across Ontario, cowbirds typically nest from May–July. Plan around that window: April for setup, July for clean-out.

Short, warm summers; Point Pelee and Long Point are continent-famous migration sites.

Brown-headed Cowbirds don't use nest boxes. Keep dense native shrubs and trees such as sugar maple, paper birch for nest sites.
Delay heavy pruning of shrubs until after July.

Native Ontario plants that attract cowbirds

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

Sugar maple

Acer saccharum · Tree

Insects, seeds and cavities.

Wild bergamot

Monarda fistulosa · Perennial

Tubular flowers for hummingbirds and seed heads for finches.

Purple coneflower

Echinacea purpurea · Perennial

Leave seed heads up through winter for goldfinches.

Black-eyed Susan

Rudbeckia hirta · Perennial

Prolific seed heads for finches and sparrows.

New England aster

Symphyotrichum novae-angliae · Perennial

Late nectar for insects and fall seed for sparrows.

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.

Paper birch

Betula papyrifera · Tree

Catkin seed feeds redpolls and siskins all winter.

Feeding cowbirds through the Ontario year

Top foods: Millet, Cracked corn.
In Ontario's winter: Cold, snowy winters; feeder flocks are dominated by chickadees, nuthatches, woodpeckers and finches.

Full diet breakdown for cowbirds · Best feeder for cowbirds

Frequently asked

Are cowbirds in Ontario year-round?

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

When do cowbirds nest in Ontario?

Nesting in Ontario typically runs May–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 Ontario?

Sugar maple, Wild bergamot, Purple coneflower, Black-eyed Susan, New England aster, Little bluestem, Tall goldenrod, Paper birch are native plants in Ontario that provide food or cover for cowbirds.

Other backyard birds in Ontario

Northern Cardinal Eastern Bluebird Black-capped Chickadee Purple Martin Downy Woodpecker Hairy Woodpecker American Goldfinch Tufted Titmouse White-breasted Nuthatch House Wren Blue Jay House Finch Purple Finch Ruby-throated Hummingbird Carolina Wren Mourning Dove American Robin Dark-eyed Junco White-throated Sparrow Song Sparrow Chipping Sparrow Red-bellied Woodpecker Northern Flicker Pileated Woodpecker Red-headed Woodpecker Yellow-bellied Sapsucker Red-breasted Nuthatch Brown Creeper Common Grackle Red-winged Blackbird Baltimore Oriole Orchard Oriole Rose-breasted Grosbeak Evening Grosbeak Pine Siskin Common Redpoll Indigo Bunting Eastern Towhee Gray Catbird Brown Thrasher Cedar Waxwing Tree Swallow Barn Swallow Eastern Phoebe Chimney Swift Yellow-rumped Warbler Pine Warbler Eastern Screech-Owl Wood Thrush Great Crested Flycatcher Eastern Kingbird American Tree Sparrow House Sparrow European Starling Canada Jay American Crow Common Raven Cooper's Hawk Sharp-shinned Hawk Red-tailed Hawk Barred Owl Great Horned Owl American Kestrel Wood Duck Wild Turkey Mallard Great Blue Heron Belted Kingfisher Scarlet Tanager Eastern Meadowlark Ruby-crowned Kinglet Golden-crowned Kinglet Hermit Thrush Winter Wren Pine Grosbeak Red Crossbill Gray Catbird Lark Sparrow Hooded Merganser Yellow Warbler Common Yellowthroat American Redstart Black-and-white Warbler Prothonotary Warbler Ovenbird Yellow-breasted Chat Orange-crowned Warbler Palm Warbler Red-eyed Vireo Warbling Vireo Eastern Wood-Pewee Least Flycatcher Cliff Swallow Northern Rough-winged Swallow Bank Swallow Common Nighthawk Eastern Whip-poor-will Canada Goose American Coot Killdeer Spotted Sandpiper American Woodcock Green Heron Great Egret Black-crowned Night Heron Turkey Vulture Osprey Bald Eagle Red-shouldered Hawk Merlin Peregrine Falcon Northern Saw-whet Owl Black-backed Woodpecker American Three-toed Woodpecker Savannah Sparrow Swamp Sparrow Vesper Sparrow Snow Bunting Lapland Longspur Horned Lark Dickcissel Common Redpoll Hoary Redpoll White-winged Crossbill Bohemian Waxwing Yellow-billed Cuckoo Bobolink Yellow-headed Blackbird Brewer's Blackbird Rusty Blackbird 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.