Oregon is home to a diverse array of bird species that nest in a variety of locations, including chimneys. Chimneys provide sheltered, dry locations for birds to build their nests and raise their young. The most common species that nest in Oregon chimneys include Chimney Swifts, European Starlings, and House Sparrows.
Chimney Swifts
The Chimney Swift is a small, cigar-shaped bird that is well adapted to utilizing chimneys for nesting and roosting. Chimney Swifts are aerial insectivores, meaning they catch and eat insects while in flight. They construct bracket-shaped nests on the inside walls of chimneys using twigs gathered in mid-air and held together with their glue-like saliva.
Chimney Swifts migrate to Oregon each spring from their wintering grounds in South America. They arrive in Oregon in April or May to breed and nest. Oregon represents the northwestern extent of their breeding range. Suitable chimney habitats for Chimney Swifts include open, unlined chimneys made of brick, stone or concrete. They prefer chimneys at least 4 feet tall and 2 feet wide.
Once a pair selects a chimney, they will construct a nest about 1/3 to 1/2 of the way down from the top. The female lays 3-5 white eggs which hatch after 18-19 days. The parents share nesting duties, rotating bringing food to the hatchlings. After a month, the young leave the nest and fly off on their own. Chimney Swifts may raise 2-3 broods per summer before migrating back to South America in October.
Where to Find Chimney Swifts in Oregon
Chimney Swifts can be found nesting in suitable chimneys across much of western and central Oregon. Some of the best places to spot them include:
- Portland metro area
- Salem
- Eugene
- Medford
- Bend
Listen for their chattering calls and watch for their fast, stiff-winged flight around chimneys at dawn and dusk.
European Starlings
European Starlings are chunky, black birds with flashy iridescent feathers. These stocky birds were introduced to North America in the late 1800s and have spread successfully across the continent.
Starlings are cavity nesters and readily use chimneys for nest sites. They compete aggressively with native birds for nesting locations. Starlings build nests of grasses, feathers, twigs and straw placed on a platform of mud or rotting wood. Typical clutch size is 4-6 pale blue eggs.
Multiple starling pairs may nest in a single chimney. Nests are often built on chimney ledges, like where the chimney meets the roof. Starlings may raise 2-3 broods per summer before gathering in large flocks in fall and winter.
Where to Find Starlings in Oregon
European Starlings utilize urban and rural habitats across Oregon. They are found year-round throughout the state, except for some remote mountainous areas. Good locations to see starlings nesting in chimneys include:
- Portland suburbs
- College campuses in Eugene and Corvallis
- Rural homesteads and farms
- Central Oregon cities like Bend and Redmond
House Sparrows
House Sparrows are another introduced cavity nesting species that readily inhabit chimneys for nesting. Native to Europe and Asia, House Sparrows were brought to North America in the 1800s. These busy birds thrive around human habitation.
House Sparrows build messy domed nests out of grass, feathers, string and litter. Nest sites include chimney cavities, holes in buildings, and nest boxes. House Sparrows may evict other birds from nest sites by destroying eggs and physically attacking the residents.
Nests contain 4-6 white eggs with faint brown spots. House Sparrows can raise 2-4 broods per season. Parents both feed nestlings a diet of seeds and insects. Look and listen for House Sparrows year-round as they chatter and forage for food around houses and settlements.
Where to Find House Sparrows in Oregon
House Sparrows live in close association with humans across Oregon. Good places to see their nests in chimneys include:
- Rural farm houses
- Urban and suburban neighborhoods
- City parks
- Schools and college campuses
Other Birds That Use Chimneys
In addition to the three species highlighted, other birds that may occasionally nest in Oregon chimneys include:
- Western Bluebirds
- Tree Swallows
- Violet-green Swallows
- American Kestrels
- Northern Flickers
Many of these species are in decline and benefit from nest boxes installed specifically for their use. Discouraging non-native species like starlings and house sparrows from utilizing chimneys can help native birds access needed nesting cavities.
Tips for Deterring Birds From Nesting in Chimneys
While seeing birds raise their young in chimneys can be charming, it can also lead to unwanted issues. Bird droppings and debris can hasten deterioration of chimneys. Nests can catch fire or emit unpleasant odors. And birds may enter living spaces through the chimney.
Here are some tips for humanely deterring birds from nesting in your chimneys:
- Install a chimney cap or vent cover to block access.
- Place a commercial chimney balloon inside the flue over winter to keep birds out when not in use.
- Hang a shiny mylar balloon or reflective tape near the top of the chimney opening.
- Install bird spikes along the top edges and sides.
- Place a plastic owl statue or predator decoy above the chimney.
- Use chemical repellents designed for chimney use.
- Hire a chimney sweep to professionally clean and install deterrents.
Take action before nesting season begins in spring for best results. Ensure all fireplaces, furnaces and wood stoves are properly maintained and cleaned before putting back into regular use.
Conclusion
Chimneys in Oregon provide convenient nesting sites for birds like Chimney Swifts, European Starlings and House Sparrows. Observing the birds and their nests can be an enjoyable part of the spring and summer. However, take steps to discourage birds if their activity becomes problematic. With some understanding of chimney-nesting bird behavior and gentle deterrents, we can prevent unwanted issues and conflicts.
