BirdAnalyst
Species · BCR 34 · BBS 2025 Release · 1966–2024

Lazuli Bunting In Sierra Madre Occidental

All regionsSierra Madre OccidentalGeneralists

Lazuli Bunting in Sierra Madre Occidental has collapsed: down 89% on the route-weighted index since 1981.

-89%Since 1981TrendPercent 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 →
9Routes 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 →
19YearsYears 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 declinecomputed 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 →

Lazuli Bunting has collapsed in Sierra Madre Occidental: down 89% on the route-weighted index since 1981.

Lazuli Bunting In Sierra Madre Occidental Population Forecast

If the recent trend holds, Lazuli Bunting in Sierra Madre Occidental is projected to stay roughly flat through 2027, near 0.00 (95% range 0.00–0.34). A 5-year backtest shows a typical error of ±288.6%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2027TrendPercent 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 →
0.00Projected 2027 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.3495% 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 →
±288.6%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, Lazuli Bunting in Sierra Madre Occidental is projected to stay roughly flat through 2027, near 0.00 (95% range 0.00–0.34). A 5-year backtest shows a typical error of ±288.6%, with 100% of held-out values landing inside the 95% band.19742027
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 →
20230.000.000.34
20240.000.000.34
20250.000.000.34
20260.000.000.34
20270.000.000.34

Routes In Sierra Madre Occidental

Routes recording Lazuli Bunting 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 →
MaineARIZONA121997
Aztec PeakARIZONA71974
FlagstaffARIZONA22000
BlueARIZONA21988
ReserveNEW-MEXICO21996
PrescottARIZONA12013
PomereneARIZONA12022
PatagoniaARIZONA12015
Carr MtnARIZONA11988

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