BirdAnalyst
Species · Maryland · BBS 2025 Release · 1966–2024

Northern Rough-winged Swallow Population Trend in Maryland

All statesAerial insectivores

Northern Rough-winged Swallow in Maryland has surged: up 88% on the route-weighted index since 1968.

+88%Since 1968
67Routes In State
58Years

Notable Northern Rough-winged Swallow Trends in Maryland

long arc increasecomputed index

Northern Rough-winged Swallow has surged in Maryland: up 87% on the route-weighted index since 1968.

Northern Rough-winged Swallow Population Forecast in Maryland

If the recent trend holds, Northern Rough-winged Swallow in Maryland is projected to fall about 15% by 2029 — from 0.74 in 2024 to a central estimate of 0.63 (95% range 0.18–1.1). A 5-year backtest shows a typical error of ±30.1%, with 100% of held-out values landing inside the 95% band.

-15%Change by 2029
0.63Projected 2029 index
0.18–1.195% range
±30.1%Backtest error
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 index95% low95% high
20250.620.171.1
20260.620.181.1
20270.620.181.1
20280.630.181.1
20290.630.181.1

Northern Rough-winged Swallow Survey Routes in Maryland

Routes recording Northern Rough-winged Swallow in Maryland.
Bachman Mill920241967
Williamsport820241966
Madonna820222011
Elkton620231969
Olney520241971
Floyd420191967
Beltsville420081966
Finzel420242002
Forest Grove420232011
Bald Friar319961996
Eklo319981971
Largo319661966
Indiantown320101979
Fair Hill319961993
Potomac Park220241971
Pleasant Val220081966
Randallstown220041974
Van Bibber220061967
Pt Republic219661966
La Plata220091969
Melitota220131966
Piney Neck220221966
Harmony220171967
Golden Hill220082001
Fruitland219981967

Northern Rough-winged Swallow Population Trend in Other States

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

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