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

Red Crossbill Population Trend in Arizona

All statesGeneralists

Red Crossbill in Arizona has edged down: down 17% on the route-weighted index since 1974.

-17%Since 1974TrendPercent 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 →
20Routes 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 →
46YearsYears 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 ArizonaNotable 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 Red Crossbill in Arizona. See the full index history below.

Red Crossbill Population Forecast in Arizona

If the recent trend holds, Red Crossbill in Arizona is projected to fall about 63% by 2029 — from 1.2 in 2024 to a central estimate of 0.45 (95% range 0.00–1.9). A 5-year backtest shows a typical error of ±122.8%, with 100% of held-out values landing inside the 95% band.

-63%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 →
0.45Projected 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 →
0.00–1.995% 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 →
±122.8%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 Arizona is projected to fall about 63% by 2029 — from 1.2 in 2024 to a central estimate of 0.45 (95% range 0.00–1.9). A 5-year backtest shows a typical error of ±122.8%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.470.001.9
20260.470.001.9
20270.460.001.9
20280.460.001.9
20290.450.001.9

Red Crossbill Survey Routes in Arizona

Routes recording Red Crossbill in Arizona.
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 →
Sawmill3820081989
Happy Jack3220241986
Maine1420162006
Prescott1020191976
Dry Park1020241992
Aztec Peak719771974
Zeniff619701970
Alpine420221993
House Rock319841978
Forest Lakes319971995
Rucker220082008
Blue219881974
Williams220182013
Pinetop220222014
Tsaile220221993
Sprucedale220151992
Portal120241982
Flagstaff120221988
Mormon Lake119751969
Clay Spring120122012

Red Crossbill Population Trend in Other States

alabamaalaskaarkansascaliforniacoloradogeorgiaidahoillinoismainemarylandmassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinanorth-dakotaoregonpennsylvaniasouth-carolinasouth-dakotatennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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