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Species · Arizona · BBS 2026 Release · 1966–2025

Great-tailed Grackle Population Trend in Arizona

All statesWetland birds

Great-tailed Grackle in Arizona has surged: up 390% on the route-weighted index since 1970.

+390%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 →
49Routes 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 Great-tailed Grackle 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 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 →

Great-tailed Grackle has surged in Arizona: up 390% on the route-weighted index since 1970.

Great-tailed Grackle Population Forecast in Arizona

If the recent trend holds, Great-tailed Grackle in Arizona is projected to rise about 248% by 2030 — from 3.5 in 2025 to a central estimate of 12 (95% range 7.0–17). A 5-year backtest shows a typical error of ±127.6%, with 0% of held-out values landing inside the 95% band.

+248%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 →
12Projected 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 →
7.0–1795% 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 →
±127.6%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, Great-tailed Grackle in Arizona is projected to rise about 248% by 2030 — from 3.5 in 2025 to a central estimate of 12 (95% range 7.0–17). A 5-year backtest shows a typical error of ±127.6%, with 0% 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 →
2026116.316
2027126.517
2028126.717
2029126.817
2030127.017

Great-tailed Grackle Survey Routes in Arizona

Routes recording Great-tailed Grackle 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 →
Laguna9020231969
Araby7120231992
Cactus Forest5020251991
Casa Grande4320231989
Hope2620091990
Palo Verde 22420252014
Palo Verde1920131992
Hope 21920192014
Florence1719881968
Vicksburg1419891988
Bartlett Res1420252007
Oatman1320251988
Cibola Lake1220241994
Red Rock 21120242015
Ajo 21120222009
Organ Pipe920231992
Seligman920251991
Riviera720252004
Pomerene520251977
Alamo Res.520181993
Mcneal520251992
Peach Spring520251992
Patagonia420251970
Pinetop420032003
Carr Mtn420211989

Great-tailed Grackle Population Trend in Other States

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