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

Cliff Swallow Population Trend in Washington

All statesAerial insectivores

Cliff Swallow in Washington has declined: down 28% on the route-weighted index since 1970.

-28%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 →
56YearsYears 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 113% by 2029 — from 14 in 2024 to a central estimate of 31 (95% range 4.4–57). A 5-year backtest shows a typical error of ±69.3%, with 100% of held-out values landing inside the 95% band.

+113%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 →
31Projected 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 →
4.4–5795% 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 →
±69.3%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 113% by 2029 — from 14 in 2024 to a central estimate of 31 (95% range 4.4–57). A 5-year backtest shows a typical error of ±69.3%, with 100% of held-out values landing inside the 95% band.19682029
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 →
2025314.457
2026314.457
2027314.457
2028314.457
2029314.457

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 Reservoir24520242009
Columbia Nwr19820221992
Mesa18520081994
Othello17219911981
Horn Rapids13820242005
Potholes12320231996
Nighthawk10720241992
Keystone6920241994
Wapato6620221972
Ewan5920191983
Brewster4920181977
Mendota4819881977
Hanford Site3719961988
Omak Creek3620241996
Pomona3419991998
Harrington3220121980
Yakima3120241993
Warm Beach 22920242018
Wilbur2820241985
Warm Beach2520171968
Selah2420232000
Mercer1620211978
Rainier1620181996
Rimrock1520241969
Laurier1520221997

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 2026-05-22.