Species · Pennsylvania · BBS 2025 Release · 1966–2024

Northern Rough-winged Swallow Population Trend in Pennsylvania

Northern Rough-winged Swallow in Pennsylvania has surged: up 84% on the route-weighted index since 1968.

+84%Since 1968
122Routes In State
58Years

Notable Northern Rough-winged Swallow Trends in Pennsylvania

long arc increasecomputed index

Northern Rough-winged Swallow has surged in Pennsylvania: up 84% on the route-weighted index since 1968.

Northern Rough-winged Swallow Population Forecast in Pennsylvania

If the recent trend holds, Northern Rough-winged Swallow in Pennsylvania is projected to fall about 23% by 2029 — from 1.5 in 2024 to a central estimate of 1.1 (95% range 0.68–1.6). A 5-year backtest shows a typical error of ±15.3%, with 100% of held-out values landing inside the 95% band.

-23%Change by 2029
1.1Projected 2029 index
0.681.695% range
±15.3%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
20251.10.651.6
20261.10.651.6
20271.10.661.6
20281.10.671.6
20291.10.681.6

Northern Rough-winged Swallow Survey Routes in Pennsylvania

Routes recording Northern Rough-winged Swallow in Pennsylvania.
Mount Joy2420241979
Brick Tavern1520241994
Beaver1220241969
Stoneybreak920221992
Betula820221989
Portersville819881988
Elizabethvil820241997
New Ringgold720241966
Schaefferstown 2720242002
Russell City620071969
Rush620241970
Doubling Gap619761966
Ramsey520231992
Pocono Summit520241994
Susquehanna520241978
Kaylor520221968
Rector519661966
Drehersville519991967
Doylesburg520232013
Eldred420082005
Marsh Hill420071985
Duvall420171977
Shelocta420241972
Carsonville420231966
West Grove419961970

Northern Rough-winged Swallow Population Trend in Other States

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