Species · Arizona · BBS 2025 Release · 1966–2024

Grace's Warbler Population Trend in Arizona

Grace's Warbler in Arizona has risen sharply: up 65% on the route-weighted index since 1970.

+65%Since 1970
23Routes In State
54Years

Notable Grace's Warbler Trends in Arizona

long arc increasecomputed index

Grace's Warbler has risen sharply in Arizona: up 65% on the route-weighted index since 1970.

Grace's Warbler Population Forecast in Arizona

If the recent trend holds, Grace's Warbler in Arizona is projected to stay roughly flat through 2029, near 2.6 (95% range 0.80–4.4). A 5-year backtest shows a typical error of ±6%, with 100% of held-out values landing inside the 95% band.

+1%Change by 2029
2.6Projected 2029 index
0.804.495% range
±6%Backtest error
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 index95% low95% high
20252.60.784.3
20262.60.784.3
20272.60.794.3
20282.60.794.4
20292.60.804.4

Grace's Warbler Survey Routes in Arizona

Routes recording Grace's Warbler in Arizona.
Happy Jack6220241977
Sawmill3720141988
Tsaile2820231993
Tonto Vill.2320211992
Sprucedale2120231992
Aztec Peak1619781974
Mt. Graham1420231995
Rucker1120091993
Alpine1020231992
Forest Lakes920241992
Flagstaff820221988
Prescott720221975
Dry Park720241992
Carr Mtn620241985
Portal520241975
Zeniff319681968
Blue319911974
Sunizona319751974
Williams320182001
Maine220211997
Pinetop220221994
Round Rock119761969
Mormon Lake119751968

Grace's Warbler Population Trend in Other States

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