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

Bank Swallow Population Trend in Wisconsin

All statesAerial insectivores

Bank Swallow in Wisconsin has collapsed: down 91% on the route-weighted index since 1968.

-91%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 →
86Routes 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 WisconsinNotable 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 Wisconsin: down 91% on the route-weighted index since 1968.

Bank Swallow Population Forecast in Wisconsin

If the recent trend holds, Bank Swallow in Wisconsin is projected to fall about 100% by 2029 — from 0.72 in 2024 to a central estimate of 0.00 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±50.1%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–3.595% 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 →
±50.1%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 Wisconsin is projected to fall about 100% by 2029 — from 0.72 in 2024 to a central estimate of 0.00 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±50.1%, 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 →
20250.120.003.6
20260.000.003.5
20270.000.003.5
20280.000.003.5
20290.000.003.5

Bank Swallow Survey Routes in Wisconsin

Routes recording Bank Swallow in Wisconsin.
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 →
Omro6820011966
Rolling Grnd3020231970
Prairie Du Chien3020151998
Mount Horeb1819901967
Irma1220001974
Hollister1220121969
Clintonville1020181967
Eden920241966
Beloit920242007
Weyerhauser820231966
Cadott820241966
Cavour820092009
Couderay620171969
Exeland620101969
Hatfield619981974
Newburg Crns620081966
Grimms620211999
Holland620102000
Dresser520211966
Cumberland520031966
Unity520091967
Elderon520121966
Oconto Falls520151970
New Lisbon520151967
N Freedom520231967

Bank Swallow Population Trend in Other States

alabamaalaskaarkansascaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawyoming

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