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

American Robin Population Trend in Arizona

All statesForest birds

American Robin in Arizona has surged: up 276% on the route-weighted index since 1970.

+276%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 →
37Routes 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 American Robin 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 →

American Robin has surged in Arizona: up 276% on the route-weighted index since 1970.

American Robin Population Forecast in Arizona

If the recent trend holds, American Robin in Arizona is projected to rise about 70% by 2029 — from 3.8 in 2024 to a central estimate of 6.5 (95% range 2.4–11). A 5-year backtest shows a typical error of ±47.7%, with 100% of held-out values landing inside the 95% band.

+70%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 →
6.5Projected 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 →
2.4–1195% 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 →
±47.7%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, American Robin in Arizona is projected to rise about 70% by 2029 — from 3.8 in 2024 to a central estimate of 6.5 (95% range 2.4–11). A 5-year backtest shows a typical error of ±47.7%, 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 →
20256.32.210
20266.42.210
20276.42.311
20286.42.311
20296.52.411

American Robin Survey Routes in Arizona

Routes recording American Robin 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 →
Happy Jack8820241977
Alpine8120231992
Tsaile6720231993
Sprucedale5520231992
Blue3419911974
Flagstaff2620221988
Mt. Graham2520231995
Pinetop2320221993
Sawmill1920141988
Dry Park1920241992
Williams1720191993
Mormon Lake1219751968
Maine1120241992
Tonto Vill.1020211992
Prescott920221974
Aztec Peak919781974
Portal820241975
Sunizona619971970
Rucker520091993
Cow Springs420221995
Skull Valley420242001
Round Rock319721968
Page320182006
House Rock220151976
Black Mesa219921988

American Robin Population Trend in Other States

alabamaalaskaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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