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

Black-chinned Hummingbird In Sierra Madre Occidental

All regionsSierra Madre OccidentalGeneralists

Black-chinned Hummingbird in Sierra Madre Occidental has collapsed: down 77% on the route-weighted index since 1970.

-77%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 →
27Routes 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 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 →

Black-chinned Hummingbird has collapsed in Sierra Madre Occidental: down 77% on the route-weighted index since 1970.

Black-chinned Hummingbird In Sierra Madre Occidental Population Forecast

If the recent trend holds, Black-chinned Hummingbird in Sierra Madre Occidental is projected to stay roughly flat through 2029, near 0.55 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±52.8%, with 100% of held-out values landing inside the 95% band.

-1%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 →
0.55Projected 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 →
0.00–1.595% 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 →
±52.8%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, Black-chinned Hummingbird in Sierra Madre Occidental is projected to stay roughly flat through 2029, near 0.55 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±52.8%, 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 →
20250.610.001.6
20260.590.001.6
20270.580.001.6
20280.560.001.5
20290.550.001.5

Routes In Sierra Madre Occidental

Routes recording Black-chinned Hummingbird 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 →
Mormon LakeARIZONA41974
Skull ValleyARIZONA42015
PomereneARIZONA32024
PatagoniaARIZONA32024
CutterARIZONA32014
RuckerARIZONA32009
Emory PassNEW-MEXICO32023
PrescottARIZONA22019
Forest LakesARIZONA22024
RedingtonARIZONA22021
McnealARIZONA22021
Clay SpringARIZONA22014
PortalARIZONA22022
DragoonARIZONA22009
Aztec PeakARIZONA11978
San SimonARIZONA12023
Peña BlancaARIZONA12009
SunizonaARIZONA11996
Tonto Vill.ARIZONA12017
PinetopARIZONA12021
Bartlett ResARIZONA12023
AmadoARIZONA12021
SahuaritaARIZONA12019
Carr MtnARIZONA12024
Sunizona 2ARIZONA12024

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