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Species · Washington · BBS 2026 Release · 1966–2025

California Quail Population Trend in Washington

All statesGame birds

California Quail in Washington has surged: up 308% on the route-weighted index since 1970.

+308%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 →
90Routes 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 California Quail 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 →

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 →

California Quail has surged in Washington: up 307% on the route-weighted index since 1970.

California Quail Population Forecast in Washington

If the recent trend holds, California Quail in Washington is projected to rise about 40% by 2030 — from 5.2 in 2025 to a central estimate of 7.2 (95% range 3.1–11). A 5-year backtest shows a typical error of ±65.6%, with 100% of held-out values landing inside the 95% band.

+40%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 →
7.2Projected 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 →
3.1–1195% 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 →
±65.6%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, California Quail in Washington is projected to rise about 40% by 2030 — from 5.2 in 2025 to a central estimate of 7.2 (95% range 3.1–11). A 5-year backtest shows a typical error of ±65.6%, 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 →
20266.92.811
20276.92.911
20287.03.011
20297.13.011
20307.23.111

California Quail Survey Routes in Washington

Routes recording California Quail 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 →
Mesa5920081994
Malden5020251998
Ewan 23520252023
Ellensburg3320251981
Wapato2620221971
Deer Park2020121994
Columbia Nwr1920221992
Brewster1820151977
Moses Lake1820221988
Nighthawk1820251992
Quincy1720241987
Pomona1719991998
Tonasket1620181982
Moses Coulee1620251993
Harwood1519971993
Othello1419911981
Lake Chelan1320251988
Chewelah1120211980
Scootney Reservoir1020252009
Wilbur920251984
Keystone920252008
Potholes920231996
Reardan820251968
Laurier820252002
Yakima820251993

California Quail Population Trend in Other States

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