House Sparrows Nesting in Signs, Awnings, Eaves and Barns

How do you tell a house sparrow from a native sparrow?

Start with the male. The Montana Field Guide describes the house sparrow as stout and stocky with short legs and a thick bill. The male has a gray crown bordered with chestnut, a white cheek and a black bib. The female is plainer: a gray-brown crown, a pale buff line over the eye, and an unmarked throat and breast. The National Audubon Society gives the size as roughly five to six and a half inches and the voice as shrill, monotonous, noisy chirping.

The female is where mistakes happen. The house sparrow chapter of the Prevention and Control of Wildlife Damage handbook, produced by the University of Nebraska with USDA, says the female and young are difficult to distinguish from some native sparrows. The Montana Field Guide lists a long roster of native New World sparrows in the state, including the song sparrow, chipping sparrow, savannah sparrow, vesper sparrow and dark-eyed junco. They belong to a different bird family from the house sparrow.

Behavior helps. Audubon notes that in North America the house sparrow is essentially always found around manmade structures and never in unaltered natural habitat, and that it often breeds in small colonies. A noisy group nesting in a sign with a black-bibbed male in attendance is a house sparrow colony. A single streaky sparrow in a hedge is something else.

Are house sparrows protected in Montana?

No. The U.S. Fish and Wildlife Service notice listing birds to which the Migratory Bird Treaty Act does not apply states that the Old World sparrow family, including the house or English sparrow, does not qualify for protection under the Act. The wildlife damage handbook says the species has no legal protection under federal statutes because it is introduced. Montana's wild bird protection statute names house sparrows first among the birds it does not cover, together with their nests and eggs.

The handbook adds that a few states restrict control activities and advises checking with state or local government first. And the other half of the rule is firm: the same Montana statute makes it unlawful to take or destroy the nest or eggs of other wild birds without a permit, and the federal Act protects native migratory species. NestWatch, a Cornell Lab of Ornithology program, puts it plainly: it is illegal to harm or harass any native species, including their nests and eggs. If the identification is in doubt, treat the bird as protected. Montana bird nest removal law explains the general rule.

Where do house sparrows nest on buildings?

In enclosed niches. The Montana Field Guide says they nest often in enclosed spaces, and Audubon lists a hole in a building, a rain gutter, a birdhouse and the nests of other birds. On a commercial building that means the hollow behind channel lettering, the top of a sign cabinet, the frame pockets of an awning, open eave ends, and the gap around a wall-mounted air conditioner.

The nest itself is the giveaway. The handbook calls it bulky and roofed, built haphazardly. Audubon says it is made of grass, weeds, twigs and trash, often lined with feathers. Inside a cavity the material forms a foundation that fills the space, and in the open it becomes a globular mass with a side entrance. Long straws trailing out of a sign are typical.

The handbook also flags a risk owners overlook: the bulky, flammable nests are a potential fire hazard. Around lit signs and fixtures, a qualified sign technician or electrician should check wiring once the nest is out.

How long is the house sparrow nesting season?

Long. The Montana Field Guide says nesting in Montana typically begins in early April and may last to mid-September, and that successful birds may have up to four clutches in a season. Audubon gives incubation as 10 to 14 days and says the young leave the nest about two weeks after hatching.

House sparrows also do not leave. Audubon calls the species a permanent resident throughout North America, and the handbook reports studies showing that 90 percent of adults stay within about a mile and a quarter during the nesting period. The birds on your sign in January are the birds that will nest in it in April, which is why winter is a good time to close the gaps.

Why do they pick storefronts, garden centers and barns?

Food within a few yards of shelter. The Montana Field Guide lists grains, weed seeds and livestock feed, and notes that urban birds eat commercial birdseed. The handbook adds that garbage, bread crumbs and refuse from fast-food restaurants can support urban populations, and that sparrows interfere with livestock production, particularly poultry, by eating and contaminating feed.

So the pattern is predictable: a garden center with open seed and a covered rafter space, a drive-through with a lit sign over a parking lot, a feed room in a barn. The handbook notes that droppings and feathers create sanitation problems inside and outside buildings and on sidewalks under roosting areas. Food businesses have more at stake, as our guide to bird control for restaurants and food businesses explains.

What gap size keeps house sparrows out?

Three quarters of an inch. The handbook says to close all openings over three-quarters of an inch to exclude house sparrows from buildings and to block larger openings with mesh no larger than that. New Mexico State University Extension gives the same figure. That is small enough that most eave gaps, vent louvers and sign cavities qualify.

The handbook then works through a building the way an installer does. Attach signs flat against the wall, and screen or block the space between existing signs and the building. Screen eaves the birds can squeeze into. Block the gap between a window air conditioner and the wall. Fit boards or metal at more than 45 degrees over ledges under overhangs. Hang plastic strip curtains across warehouse doorways that must stay open. Our bird netting and exclusion crews do this on storefronts, and barn bird control covers feed rooms and rafters.

Do scare devices or feeder changes help?

Scare devices, no. New Mexico State University Extension states that frightening devices have little or no effect on house sparrows and pigeons. These birds live beside traffic and people all day.

Food changes can help at the margins. NestWatch notes that house sparrows prefer small seeds such as millet, cracked corn and milo, which are plentiful in inexpensive seed mixes, and suggests avoiding seed scattered on the ground. Feeders with short perches and small ports are also less attractive to them.

Can the nests simply be pulled out?

For a confirmed house sparrow, the law does not prevent it. But removal without closing the cavity achieves little. NestWatch describes house sparrows rebuilding repeatedly, and warns that birds pushed out of one site may take over another that holds an active native nest. The cavity has to be emptied and closed in the same visit.

We also check what else is using the structure. Swallows build on the same walls and are protected, as covered in our barn swallow exclusion guide. Our bird nest removal service clears confirmed house sparrow nests and debris with protective equipment and contained disposal, then screens the opening.

What should a business or homeowner do first?

Count the entry points. Every gap over three-quarters of an inch on a sign, awning or eave is a candidate, and closing only the one in use moves the colony a few feet. A bird mitigation assessment maps them and confirms the species before anything is touched. Related species are in the Montana Bird Control Guide.

Call HJ Property Care & Tree Service at (406) 215-7319 or request a bird assessment and we will identify the species, the access points, and what will actually stop them.

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