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

Red Crossbill Population Trend in Washington

All statesGeneralists

Red Crossbill in Washington has risen sharply: up 62% on the route-weighted index since 1970.

+62%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 →
78Routes 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 Red Crossbill 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 →

Red Crossbill has risen sharply in Washington: up 62% on the route-weighted index since 1970.

Red Crossbill Population Forecast in Washington

If the recent trend holds, Red Crossbill in Washington is projected to rise about 166% by 2029 — from 1.8 in 2024 to a central estimate of 4.8 (95% range 0.00–10). A 5-year backtest shows a typical error of ±50.3%, with 80% of held-out values landing inside the 95% band.

+166%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 →
4.8Projected 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 →
0.00–1095% 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 →
±50.3%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, Red Crossbill in Washington is projected to rise about 166% by 2029 — from 1.8 in 2024 to a central estimate of 4.8 (95% range 0.00–10). A 5-year backtest shows a typical error of ±50.3%, with 80% 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 →
20254.80.0010.0
20264.80.0010
20274.80.0010
20284.80.0010
20294.80.0010

Red Crossbill Survey Routes in Washington

Routes recording Red Crossbill 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 →
Taholah14020221969
Hurricane Rg5520231992
Mendota 24219961990
L Pend O Nwr3620241995
Mukilteo3520151994
Neilton3219751975
Ozette2520221974
Wilbur2320221984
Laurier2120222000
Turnbull Nwr2120211993
Keller1820071968
Camas1820051986
Mazama1620221993
Cusick1420231982
Index 21320222015
Snowden1220222000
Issaquah1019871984
Ilwaco1020241976
Spring Lake1020231985
Cedar Falls920131997
Mt St Helens820211992
Cascade Riv820001988
Blewett Pass720221992
Deer Park720151994
Mt. Adams720241994

Red Crossbill Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradogeorgiaidahoillinoismainemarylandmassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinanorth-dakotaoregonpennsylvaniasouth-carolinasouth-dakotatennesseeutahvermontvirginiawest-virginiawisconsinwyoming

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