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Species · Massachusetts · BBS 2025 Release · 1966–2024

Northern Rough-winged Swallow Population Trend in Massachusetts

All statesAerial insectivores

Northern Rough-winged Swallow in Massachusetts has edged up: up 24% on the route-weighted index since 1970.

+24%Since 1970TrendPercent 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 →
29Routes 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 →
56YearsYears 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 MassachusettsNotable 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 Massachusetts. See the full index history below.

Northern Rough-winged Swallow Population Forecast in Massachusetts

If the recent trend holds, Northern Rough-winged Swallow in Massachusetts is projected to fall about 48% by 2029 — from 0.80 in 2024 to a central estimate of 0.42 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±249.9%, with 100% of held-out values landing inside the 95% band.

-48%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 →
0.42Projected 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 →
0.00–1.195% 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 →
±249.9%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 Massachusetts is projected to fall about 48% by 2029 — from 0.80 in 2024 to a central estimate of 0.42 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±249.9%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.420.001.1
20260.420.001.1
20270.420.001.1
20280.420.001.1
20290.420.001.1

Northern Rough-winged Swallow Survey Routes in Massachusetts

Routes recording Northern Rough-winged Swallow in Massachusetts.
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 →
Mansfield1020241987
E Pepperell419921981
Cummington420091970
Pittsfield420161989
Ware River320051994
Sheffield320131969
N Oxford220171970
N Orange219791978
Cheshire219931993
Hancock220002000
E Dennis119841973
Chilmark119811981
Marion120131978
Wellfleet119971992
Prattville120131967
Brockton120181985
Maynard119931990
Littleton119971975
Princeton119761972
Belchertown120171973
Warren120091969
S Barre119921969
Chesterfield120191998
Cape Cod Ns119961995
Gay Head120121996

Northern Rough-winged Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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