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

Lucy's Warbler Population Trend in Arizona

All statesArid-land birds

Lucy's Warbler in Arizona has edged up: up 12% on the route-weighted index since 1970.

+12%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 →
54Routes 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 Lucy's Warbler 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 Lucy's Warbler in Arizona. See the full index history below.

Lucy's Warbler Population Forecast in Arizona

If the recent trend holds, Lucy's Warbler in Arizona is projected to fall about 21% by 2029 — from 12 in 2024 to a central estimate of 9.8 (95% range 2.2–17). A 5-year backtest shows a typical error of ±16%, with 100% of held-out values landing inside the 95% band.

-21%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 →
9.8Projected 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 →
2.2–1795% 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 →
±16%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, Lucy's Warbler in Arizona is projected to fall about 21% by 2029 — from 12 in 2024 to a central estimate of 9.8 (95% range 2.2–17). A 5-year backtest shows a typical error of ±16%, 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 →
20259.82.317
20269.82.317
20279.82.217
20289.82.217
20299.82.217

Lucy's Warbler Survey Routes in Arizona

Routes recording Lucy's Warbler 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 →
Pomerene17320241968
Redington7720231993
Cutter 26820182015
Patagonia6220241968
Cutter4720141992
Peña Blanca4420241975
Sahuarita3920241992
Wikieup3720241992
Amado3720231993
Bartlett Res1620241993
Wickenburg1620232017
Carr Mtn1620241985
Lukeville1319801975
New River1220161974
San Simon1220241969
Organ Pipe1020231990
Florence919881968
Red Rock 2720242015
Skull Valley720241997
Dateland520211991
Coolidge519851978
Riviera520241992
Sunizona419971970
Alamo Res.420231993
Cibola Lake420241993

Lucy's Warbler Population Trend in Other States

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