New Brunswick · Year-round resident

Brown-headed Cowbirds in New Brunswick

When cowbirds are present in New Brunswick, when they nest, which native New Brunswick plants feed them, and how to host them in a Canada 3a–5b yard.

Blackbirds (Icteridae)Brown-headed CowbirdMolothrus ater

Status in New Brunswick: Year-round resident
Nesting window: May–July
Broods: —
Hardiness zones: Canada 3a–5b

When to expect cowbirds in New Brunswick

Brown-headed Cowbirds live in New Brunswick all year. Cold, snowy winters. That makes the cold months the time your yard matters most to them.

Humid continental with Bay of Fundy and Gulf of St. Lawrence coastlines and extensive forest.

Nesting in New Brunswick

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

Mild summers.

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

Native New Brunswick plants that attract cowbirds

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

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.

Sugar maple

Acer saccharum · Tree

Hosts hundreds of caterpillar species; spring flowers draw early insects.

Red maple

Acer rubrum · Tree

Among the first spring bloomers; early insects for returning migrants.

Willow (Bebb)

Salix bebbiana · Shrub

Early catkins draw insects for arriving warblers and hummingbirds.

Feeding cowbirds through the New Brunswick year

Top foods: Millet, Cracked corn.
In New Brunswick's winter: Cold, snowy winters.

Full diet breakdown for cowbirds · Best feeder for cowbirds

Frequently asked

Are cowbirds in New Brunswick year-round?

Yes. Brown-headed Cowbirds are year-round residents in New Brunswick.

When do cowbirds nest in New Brunswick?

Nesting in New Brunswick 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 New Brunswick?

Black-eyed Susan, New England aster, Little bluestem, Tall goldenrod, Paper birch, Sugar maple, Red maple, Willow (Bebb) are native plants in New Brunswick that provide food or cover for cowbirds.

Other backyard birds in New Brunswick

Northern Cardinal Eastern Bluebird Black-capped Chickadee Purple Martin Downy Woodpecker Hairy Woodpecker American Goldfinch White-breasted Nuthatch House Wren Purple Finch Ruby-throated Hummingbird Mourning Dove American Robin Dark-eyed Junco White-throated Sparrow Song Sparrow Chipping Sparrow Northern Flicker Pileated Woodpecker Yellow-bellied Sapsucker Red-breasted Nuthatch Brown Creeper Common Grackle Red-winged Blackbird Baltimore Oriole Rose-breasted Grosbeak Evening Grosbeak Pine Siskin Common Redpoll Indigo Bunting Gray Catbird Cedar Waxwing Tree Swallow Barn Swallow Eastern Phoebe Chimney Swift Yellow-rumped Warbler 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 Ruby-crowned Kinglet Golden-crowned Kinglet Hermit Thrush Winter Wren Pine Grosbeak Red Crossbill Gray Catbird Hooded Merganser Yellow Warbler Common Yellowthroat American Redstart Black-and-white Warbler Ovenbird 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 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 Horned Lark Common Redpoll Hoary Redpoll White-winged Crossbill Bohemian Waxwing Bobolink 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.