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

Hepatic Tanager In Sierra Madre Occidental

All regionsSierra Madre OccidentalGeneralists

Hepatic Tanager in Sierra Madre Occidental has surged: up 102% on the route-weighted index since 1971.

+102%Since 1971TrendPercent 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 →
30Routes 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 →
54YearsYears 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 →

Hepatic Tanager has surged in Sierra Madre Occidental: up 102% on the route-weighted index since 1971.

Hepatic Tanager In Sierra Madre Occidental Population Forecast

If the recent trend holds, Hepatic Tanager in Sierra Madre Occidental is projected to stay roughly flat through 2029, near 2.0 (95% range 1.2–2.9). A 5-year backtest shows a typical error of ±26.8%, with 80% of held-out values landing inside the 95% band.

+8%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 →
2.0Projected 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 →
1.2–2.995% 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 →
±26.8%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, Hepatic Tanager in Sierra Madre Occidental is projected to stay roughly flat through 2029, near 2.0 (95% range 1.2–2.9). A 5-year backtest shows a typical error of ±26.8%, with 80% 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 →
20252.01.12.9
20262.01.12.9
20272.01.12.9
20282.01.12.9
20292.01.22.9

Routes In Sierra Madre Occidental

Routes recording Hepatic Tanager 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 →
Happy JackARIZONA122024
RuckerARIZONA92009
FlagstaffARIZONA72022
PortalARIZONA72024
ReserveNEW-MEXICO72023
MaineARIZONA42001
Forest LakesARIZONA42024
Clay SpringARIZONA42024
DragoonARIZONA42009
BlueARIZONA31989
Tonto Vill.ARIZONA32021
PrescottARIZONA22022
Aztec PeakARIZONA21978
Peña BlancaARIZONA22024
SunizonaARIZONA21980
Skull ValleyARIZONA22011
PinetopARIZONA22022
SprucedaleARIZONA22023
Emory PassNEW-MEXICO22024
Mormon LakeARIZONA11975
PatagoniaARIZONA12024
WilliamsARIZONA12018
AlpineARIZONA12015
RedingtonARIZONA12011
Mt. GrahamARIZONA12023

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