BirdAnalyst
Species · Washington · BBS 2026 Release · 1966–2025

Cliff Swallow Population Trend in Washington

All statesAerial insectivores

Cliff Swallow in Washington has declined: down 29% on the route-weighted index since 1970.

-29%Since 1970TrendPercent 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 →
96Routes 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 →
57YearsYears 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 WashingtonNotable 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 Washington. See the full index history below.

Cliff Swallow Population Forecast in Washington

If the recent trend holds, Cliff Swallow in Washington is projected to rise about 58% by 2030 — from 19 in 2025 to a central estimate of 30 (95% range 3.6–56). A 5-year backtest shows a typical error of ±78.5%, with 100% of held-out values landing inside the 95% band.

+58%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 →
30Projected 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 →
3.6–5695% 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 →
±78.5%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 Washington is projected to rise about 58% by 2030 — from 19 in 2025 to a central estimate of 30 (95% range 3.6–56). A 5-year backtest shows a typical error of ±78.5%, with 100% of held-out values landing inside the 95% band.19682030
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 →
2026303.756
2027303.656
2028303.656
2029303.656
2030303.656

Cliff Swallow Survey Routes in Washington

Routes recording Cliff Swallow in Washington.
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 →
Scootney Reservoir38420252009
Columbia Nwr19820221992
Mesa18520081994
Othello17219911981
Horn Rapids13820242005
Yakima13120251993
Potholes12320231996
Nighthawk9420251992
Wapato6620221972
Ewan5920191983
Brewster4920181977
Mendota4819881977
Keystone4820251994
Selah4020252000
Malden3920251998
Odessa3720251993
Hanford Site3719961988
Omak Creek3620241996
Pomona3419991998
Harrington3220121980
Ewan 23120252023
Warm Beach 22920242018
Warm Beach2520171968
Moses Coulee2020251993
Reardan1620251968

Cliff Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

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