BirdAnalyst
Species · BCR 34 · BBS 2026 Release · 1966–2025

Red-faced Warbler In Sierra Madre Occidental

All regionsSierra Madre OccidentalForest birds

Red-faced Warbler in Sierra Madre Occidental has surged: up 209% on the route-weighted index since 1970.

+209%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 →
18Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
55YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 →

Red-faced Warbler has surged in Sierra Madre Occidental: up 209% on the route-weighted index since 1970.

Red-faced Warbler In Sierra Madre Occidental Population Forecast

If the recent trend holds, Red-faced Warbler in Sierra Madre Occidental is projected to rise about 13% by 2030 — from 2.1 in 2025 to a central estimate of 2.4 (95% range 0.38–4.5). A 5-year backtest shows a typical error of ±32.3%, with 100% of held-out values landing inside the 95% band.

+13%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 →
2.4Projected 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 →
0.38–4.595% 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 →
±32.3%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, Red-faced Warbler in Sierra Madre Occidental is projected to rise about 13% by 2030 — from 2.1 in 2025 to a central estimate of 2.4 (95% range 0.38–4.5). A 5-year backtest shows a typical error of ±32.3%, with 100% 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 →
20262.40.364.5
20272.40.364.5
20282.40.374.5
20292.40.374.5
20302.40.384.5

Routes In Sierra Madre Occidental

Routes recording Red-faced Warbler in Sierra Madre Occidental.
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 →
Mt. GrahamARIZONA302025
Emory PassNEW-MEXICO112025
ReserveNEW-MEXICO92023
PrescottARIZONA72025
FlagstaffARIZONA61988
Happy JackARIZONA52025
AlpineARIZONA22025
PortalARIZONA22025
RuckerARIZONA22004
Vicks PeakNEW-MEXICO22005
Mormon LakeARIZONA11974
Aztec PeakARIZONA11978
BlueARIZONA11990
WilliamsARIZONA12025
Tonto Vill.ARIZONA12021
PinetopARIZONA12021
Carr MtnARIZONA12017
SprucedaleARIZONA12021

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