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

Cliff Swallow Population Trend in Kentucky

All statesAerial insectivores

Cliff Swallow in Kentucky has surged: up 77× on the route-weighted index since 1979.

77×Since 1979TrendPercent 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 →
29Routes 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 →
46YearsYears 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 KentuckyNotable 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 Kentucky: up 77× on the route-weighted index since 1979.

Cliff Swallow Population Forecast in Kentucky

If the recent trend holds, Cliff Swallow in Kentucky is projected to rise about 20% by 2029 — from 8.9 in 2024 to a central estimate of 11 (95% range 5.4–16). A 5-year backtest shows a typical error of ±17.9%, with 80% of held-out values landing inside the 95% band.

+20%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 →
11Projected 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 →
5.4–1695% 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 →
±17.9%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 Kentucky is projected to rise about 20% by 2029 — from 8.9 in 2024 to a central estimate of 11 (95% range 5.4–16). A 5-year backtest shows a typical error of ±17.9%, with 80% of held-out values landing inside the 95% band.19712029
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 →
20259.84.515
2026104.715
2027104.916
2028115.216
2029115.416

Cliff Swallow Survey Routes in Kentucky

Routes recording Cliff Swallow in Kentucky.
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 →
Riverqueen7120242012
Hustonville5020242001
Shiloh4720241979
Lovelacevile3620242005
East Union3020221999
Campton1620211979
Merrimac1220242010
Hodgenville 21220232008
Gatewood1020182015
Joy1020221990
Plum920242018
Apex820242007
Mckee820232023
Kehoe719921992
Cumberlnd Gp520051994
Keysburg520241971
Sulphur Lick420242011
Levee 2420072007
Canton320242012
Daniel Boone319881985
Porter320232002
Bardwell 2320232021
Million 2320242013
Pleasurevill220222019
Eastview220242012

Cliff Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaslouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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