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Species · Virginia · BBS 2025 Release · 1966–2024

Northern Rough-winged Swallow Population Trend in Virginia

All statesAerial insectivores

Northern Rough-winged Swallow in Virginia has edged down: down 15% on the route-weighted index since 1968.

-15%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 →
66Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Northern Rough-winged Swallow Trends in VirginiaNotable 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 Northern Rough-winged Swallow in Virginia. See the full index history below.

Northern Rough-winged Swallow Population Forecast in Virginia

If the recent trend holds, Northern Rough-winged Swallow in Virginia is projected to fall about 50% by 2029 — from 1.2 in 2024 to a central estimate of 0.58 (95% range 0.00–1.8). A 5-year backtest shows a typical error of ±28%, with 100% of held-out values landing inside the 95% band.

-50%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 →
0.58Projected 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 →
0.00–1.895% 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 →
±28%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, Northern Rough-winged Swallow in Virginia is projected to fall about 50% by 2029 — from 1.2 in 2024 to a central estimate of 0.58 (95% range 0.00–1.8). A 5-year backtest shows a typical error of ±28%, 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 →
20250.660.001.9
20260.640.001.8
20270.620.001.8
20280.600.001.8
20290.580.001.8

Northern Rough-winged Swallow Survey Routes in Virginia

Routes recording Northern Rough-winged Swallow in Virginia.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Dryden1320051991
Backbay1019661966
Finchley820152007
Blacksburg820241988
Shipman620241971
Saltville620241970
Moran620241997
Gladys620242000
Isom520241969
Big Island420241968
Quinby419951966
Marion419821977
Iron Mountain 3420172017
Taylorstown 2420132012
Iron Mtn.420061997
David320001977
Carters Brdg320101966
Hall320191967
Truhart320152002
Brodnax320241973
Cornland320002000
Pine Mtn.320241996
Shenandoa Np320232023
Gloucester320122003
Taylorstown220081967

Northern Rough-winged Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontwashingtonwest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.