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

Gray Partridge Population Trend in Washington

All statesGeneralists

Gray Partridge in Washington has fallen sharply: down 56% on the route-weighted index since 1971.

-56%Since 1971TrendPercent 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 →
23Routes 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 →
47YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Gray Partridge 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 declinecomputed 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 →

Gray Partridge has fallen sharply in Washington: down 56% on the route-weighted index since 1971.

Gray Partridge Population Forecast in Washington

If the recent trend holds, Gray Partridge in Washington is projected to fall about 66% by 2029 — from 0.09 in 2024 to a central estimate of 0.03 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±48.9%, with 100% of held-out values landing inside the 95% band.

-66%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 →
0.03Projected 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 →
0.00–0.2495% 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 →
±48.9%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, Gray Partridge in Washington is projected to fall about 66% by 2029 — from 0.09 in 2024 to a central estimate of 0.03 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±48.9%, 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 →
20250.040.000.26
20260.040.000.25
20270.040.000.25
20280.030.000.24
20290.030.000.24

Gray Partridge Survey Routes in Washington

Routes recording Gray Partridge 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 →
Harrington1020041977
Moses Lake420092005
Connell319881988
Ewan319951985
Keystone320231996
Brewster220151977
Selah220012001
Reardan220241968
Asotin220241971
Tonasket219911991
Hartline220211999
Malden220051998
Moses Coulee220211995
Mercer120181978
Sulphur120022001
Quincy119981982
Wilbur120161983
Prescott120221984
Nighthawk120242015
Waitsburg120012001
Pomeroy120222005
Odessa120212000
Cloverland120142010

Gray Partridge Population Trend in Other States

idahoillinoisindianaiowaminnesotamontananebraskanevadanew-yorknorth-dakotaoregonsouth-dakotautahwisconsinwyoming

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