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

Summer Tanager In Sierra Madre Occidental

All regionsSierra Madre OccidentalGeneralists

Summer Tanager in Sierra Madre Occidental has edged up: up 14% on the route-weighted index since 1970.

+14%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 →
23Routes 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 →
56YearsYears 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 →

No notable trend signals for Summer Tanager in Sierra Madre Occidental. See the full index history below.

Forecast

If the recent trend holds, Summer Tanager in Sierra Madre Occidental is projected to fall about 36% by 2029 — from 1.7 in 2024 to a central estimate of 1.1 (95% range 0.27–1.9). A 5-year backtest shows a typical error of ±31%, with 80% of held-out values landing inside the 95% band.

-36%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 →
1.1Projected 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 →
0.27–1.995% 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 →
±31%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, Summer Tanager in Sierra Madre Occidental is projected to fall about 36% by 2029 — from 1.7 in 2024 to a central estimate of 1.1 (95% range 0.27–1.9). A 5-year backtest shows a typical error of ±31%, 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 →
20251.10.281.9
20261.10.281.9
20271.10.281.9
20281.10.281.9
20291.10.271.9

Routes In Sierra Madre Occidental

Routes recording Summer 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 →
PatagoniaARIZONA102024
PomereneARIZONA72024
AmadoARIZONA42023
Peña BlancaARIZONA32024
Skull ValleyARIZONA32024
CutterARIZONA32014
RedingtonARIZONA32021
BlueARIZONA21986
SunizonaARIZONA21997
SahuaritaARIZONA22024
SprucedaleARIZONA22023
PortalARIZONA22024
DragoonARIZONA22009
RuckerARIZONA22001
Emory PassNEW-MEXICO22024
PrescottARIZONA12019
MaineARIZONA11993
Bartlett ResARIZONA12022
McnealARIZONA12022
Carr MtnARIZONA12024
Sunizona 2ARIZONA12024
ReserveNEW-MEXICO12023
MagdalenaNEW-MEXICO12006

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