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Species · Wisconsin · BBS 2026 Release · 1966–2025

Cliff Swallow Population Trend in Wisconsin

All statesAerial insectivores

Cliff Swallow in Wisconsin has edged down: down 21% on the route-weighted index since 1968.

-21%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 →
94Routes 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 →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Cliff 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 →

No notable trend signals for Cliff Swallow in Wisconsin. See the full index history below.

Cliff Swallow Population Forecast in Wisconsin

If the recent trend holds, Cliff Swallow in Wisconsin is projected to fall about 45% by 2030 — from 10 in 2025 to a central estimate of 5.7 (95% range 0.00–17). A 5-year backtest shows a typical error of ±49%, with 100% of held-out values landing inside the 95% band.

-45%Change by 2030TrendPercent 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 →
5.7Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1795% 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 →
±49%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, Cliff Swallow in Wisconsin is projected to fall about 45% by 2030 — from 10 in 2025 to a central estimate of 5.7 (95% range 0.00–17). A 5-year backtest shows a typical error of ±49%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20266.60.0018
20276.40.0018
20286.20.0018
20296.00.0017
20305.70.0017

Cliff Swallow Survey Routes in Wisconsin

Routes recording Cliff 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 →
Newburg Crns7520251974
Kendall6520251967
Annaton6220251998
Hudson5820251967
N Andover5620251967
Esdaile4820251972
Stratford4120251966
Trempealeau3720251967
Mather3520231969
Holway3419881967
Omro 23020252002
Clintonville2920251967
New Lisbon2820251967
Buena Vista2720251998
Hazel Green2620251966
Bashaw2620251999
Briggsville2620251999
Loraine2220211966
Beloit1920252002
Gresham1820251998
Stevens Pt1620141966
Manitowoc1520241967
Highland1520251998
Casco1420251966
Viroqua1420241979

Cliff Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.