BirdAnalyst
Species · BCR 23 · BBS 2026 Release · 1966–2025

Cliff Swallow In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionAerial insectivores

Cliff Swallow in Prairie Hardwood Transition has surged: up 138% on the route-weighted index since 1968.

+138%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 →
142Routes In RegionSurvey 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 SignalsNotable 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 increasecomputed 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 →

Cliff Swallow has surged in Prairie Hardwood Transition: up 138% on the route-weighted index since 1968.

Cliff Swallow In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Cliff Swallow in Prairie Hardwood Transition is projected to rise about 30% by 2030 — from 11 in 2025 to a central estimate of 14 (95% range 11–18). A 5-year backtest shows a typical error of ±18.2%, with 80% of held-out values landing inside the 95% band.

+30%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 →
14Projected 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 →
11–1895% 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 →
±18.2%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 Prairie Hardwood Transition is projected to rise about 30% by 2030 — from 11 in 2025 to a central estimate of 14 (95% range 11–18). A 5-year backtest shows a typical error of ±18.2%, with 80% 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 →
2026149.817
20271410.017
2028141018
2029141018
2030141118

Routes In Prairie Hardwood Transition

Routes recording Cliff Swallow in Prairie Hardwood Transition.
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 →
CaledoniaMINNESOTA1262010
Whitewater 2MINNESOTA842019
Newburg CrnsWISCONSIN752025
Lake GalenaILLINOIS742021
EdwardsMINNESOTA722024
KendallWISCONSIN652025
AnnatonWISCONSIN622025
HudsonWISCONSIN582025
N AndoverWISCONSIN562025
EsdaileWISCONSIN482025
FestinaIOWA452025
MillvilleMINNESOTA442025
Money CreekMINNESOTA422025
StratfordWISCONSIN412025
TrempealeauWISCONSIN372025
MatherWISCONSIN352023
HolwayWISCONSIN341988
Sherburne NrMINNESOTA322024
GuilfordILLINOIS302023
Omro 2WISCONSIN302025
OsseoMINNESOTA292025
ClintonvilleWISCONSIN292025
New LisbonWISCONSIN282025
Buena VistaWISCONSIN272025
Hazel GreenWISCONSIN262025

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