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Species · Arizona · BBS 2025 Release · 1966–2024

Cassin's Finch Population Trend in Arizona

All statesGeneralists

Cassin's Finch in Arizona has collapsed: down 79% on the route-weighted index since 1992.

-79%Since 1992TrendPercent 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 →
7Routes 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 →
29YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Cassin's Finch 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 →

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 →

Cassin's Finch has collapsed in Arizona: down 79% on the route-weighted index since 1992.

Cassin's Finch Population Forecast in Arizona

If the recent trend holds, Cassin's Finch in Arizona is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.15). A 5-year backtest shows a typical error of ±67.5%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.04Projected 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 →
0.00–0.1595% 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 →
±67.5%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, Cassin's Finch in Arizona is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.15). A 5-year backtest shows a typical error of ±67.5%, with 100% of held-out values landing inside the 95% band.19882029
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 →
20250.050.000.15
20260.050.000.15
20270.050.000.15
20280.050.000.15
20290.040.000.15

Cassin's Finch Survey Routes in Arizona

Routes recording Cassin's Finch 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 →
Tsaile220182017
Pinetop119931993
Sawmill120101988
Happy Jack120022002
Dry Park120241992
Clay Spring119901990
Greasewood120032003

Cassin's Finch Population Trend in Other States

californiacoloradoidahomontananevadanew-mexicooregonsouth-dakotautahwashingtonwyoming

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