BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Barn Swallow

HirundinidaeAerial insectivoresHirundo rustica

Barn Swallow has declined: down 26% on the route-weighted index since 1968.

-26%Since 1968TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
3,907RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Barn Swallow

The most widespread swallow in the world, the deeply fork-tailed Barn Swallow nests on barns, bridges and buildings and hunts insects low over fields and water.

Size
6–8 in long, about 0.7 oz (15–20 cm, 19 g)
Habitat
Open airspace over fields, water and towns; nests in cavities, earthen banks or on structures.
Diet
Flying insects caught on the wing over fields and water.
Range
Recorded on 3,907 Breeding Bird Survey routes across 49 states, most concentrated in the Appalachian Mountains.
Family
Hirundinidae · Aerial insectivores
Conservation
Least Concern

Notable Barn Swallow TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Barn Swallow. See the full index history below.

Barn Swallow Population Forecast

If the recent trend holds, Barn Swallow is projected to stay roughly flat through 2029, near 10 (95% range 7.0–14). A 5-year backtest shows a typical error of ±7.8%, with 100% of held-out values landing inside the 95% band.

-5%Change by 2029TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
10Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
7.0–1495% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±7.8%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Barn Swallow is projected to stay roughly flat through 2029, near 10 (95% range 7.0–14). A 5-year backtest shows a typical error of ±7.8%, with 100% of held-out values landing inside the 95% band.19662029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
2025117.514
2026117.414
2027117.214
2028117.114
2029107.014

Where the Barn Swallow Is Detected

BBS routes recording Barn Swallow, sized by most recent count.

Barn Swallow Population Trend by State

Barn Swallow population trend by state.
TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Alabama+176%1968108
Alaska-99%197322
Arizona+233%197160
Arkansas+92%196958
California+90%1970193
Colorado-47%1970140
Connecticut+18%196820
Delaware+96%196817
Florida14×196994
Georgia43×1968107
Idaho-71%197056
Illinois+10%1968105
Indiana+40%196868
Iowa+16%196939
Kansas-19%196967
Kentucky-39%196864
Louisiana50×196996
Maine-90%196873
Maryland-23%196876
Massachusetts-44%196832
Michigan-29%196897
Minnesota-5%196989
Mississippi+76%196873
Missouri-28%196995
Montana-18%1970100
Nebraska+16%196976
Nevada+353%197042
New Hampshire-77%196826
New Jersey-16%196842
New Mexico-29%197079
New York-34%1968128
North Carolina+186%1968107
North Dakota+2%196951
Ohio+73%196889
Oklahoma-17%196970
Oregon-28%1970114
Pennsylvania-21%1968134
Rhode Island-23%19687
South Carolina+398%196849
South Dakota-2%196965
Tennessee-35%196853
Texas+281%1969242
Utah+72%197087
Vermont-79%196826
Virginia-46%196882
Washington-37%1970103
West Virginia-35%196863
Wisconsin+10%196898
Wyoming+90%1970125

Barn Swallow Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Barn Swallow population trend by Bird Conservation Region.
TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Northern Pacific Rainforest-41%1970123
Great Basin+13%1970231
Northern Rockies-51%1970183
Prairie Potholes-3%1969124
Boreal Hardwood Transition-75%1968113
Lower Great Lakes / St. Lawrence Plain-2%196886
Atlantic Northern Forest-83%1968150
Sierra Nevada-76%197025
Southern Rockies / Colorado Plateau-41%1970185
Badlands and Prairies-9%1969136
Shortgrass Prairie+146%1969134
Central Mixed Grass Prairie-21%1969129
Edwards Plateau71×197120
Oaks and Prairies+100%196974
Eastern Tallgrass Prairie+27%1968278
Prairie Hardwood Transition+41%1968161
Central Hardwoods-36%1968163
West Gulf Coastal Plain / Ouachitas+63%1969107
Mississippi Alluvial Valley-13%196872
Southeastern Coastal Plain+146%1968333
Appalachian Mountains-18%1968390
Piedmont-3%1968168
New England / Mid-Atlantic Coast-35%1968163
Peninsular Florida+500%196953
Coastal California+206%197094
Sonoran and Mojave Deserts-19%197055
Sierra Madre Occidental+77%197328
Chihuahuan Desert+68%196953
Tamaulipan Brushlands-31%197128
Gulf Coastal Prairie37×197047

Barn Swallow Conservation Status

Least Concern

The IUCN Red List rates this species as Least Concern. Our route-weighted index shows it down about 26% since 1968. Aerial insectivores have fallen sharply across the continent, a decline widely linked to dwindling insect prey.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.