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

Bank Swallow Population Trend in Pennsylvania

All statesAerial insectivores

Bank Swallow in Pennsylvania has collapsed: down 85% on the route-weighted index since 1968.

-85%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 →
60Routes 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 Bank Swallow Trends in PennsylvaniaNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Bank Swallow has collapsed in Pennsylvania: down 84% on the route-weighted index since 1968.

Bank Swallow Population Forecast in Pennsylvania

If the recent trend holds, Bank Swallow in Pennsylvania is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.83). A 5-year backtest shows a typical error of ±167.4%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.00Projected 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 →
0.00–0.8395% 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 →
±167.4%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, Bank Swallow in Pennsylvania is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.83). A 5-year backtest shows a typical error of ±167.4%, 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 →
20250.050.000.88
20260.030.000.86
20270.010.000.84
20280.000.000.83
20290.000.000.83

Bank Swallow Survey Routes in Pennsylvania

Routes recording Bank Swallow in Pennsylvania.
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 →
Mifflintown2119861986
English Ctr1519751975
Ryde1219931992
Hop Bottom820051967
Betula720221975
Rosecrans620211969
Duvall519841982
Munson519841979
Geeseytown519891987
Slippery Rk419881976
Mars419951991
Austinville420161968
Patton419811981
Harmonsburg320142010
Berwick320071988
Roulette320131970
Arnot319801970
Honesdale320111972
Canadensis319711970
Susquehanna320101978
Garrett320161985
Clover220241990
N Washington220131968
Cherry Sprs220101995
Starlight219991970

Bank Swallow Population Trend in Other States

alabamaalaskaarkansascaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonrhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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