BirdAnalyst
Species · BCR 16 · BBS 2025 Release · 1966–2024

Summer Tanager In Southern Rockies / Colorado Plateau

All regionsSouthern Rockies / Colorado PlateauGeneralists

Summer Tanager in Southern Rockies / Colorado Plateau has fallen sharply: down 63% on the route-weighted index since 1992.

-63%Since 1992TrendPercent 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 →
5Routes 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 →
18YearsYears 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 Southern Rockies / Colorado Plateau. See the full index history below.

Summer Tanager In Southern Rockies / Colorado Plateau Population Forecast

If the recent trend holds, Summer Tanager in Southern Rockies / Colorado Plateau is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.01). A 5-year backtest shows a typical error of ±102.7%, with 80% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0195% 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 →
±102.7%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 Southern Rockies / Colorado Plateau is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.01). A 5-year backtest shows a typical error of ±102.7%, with 80% of held-out values landing inside the 95% band.19702028
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 →
20240.000.000.02
20250.000.000.02
20260.000.000.01
20270.000.000.01
20280.000.000.01

Routes In Southern Rockies / Colorado Plateau

Routes recording Summer Tanager in Southern Rockies / Colorado Plateau.
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 →
Peach SpringARIZONA12023
La CienegaNEW-MEXICO12014
ValenciaNEW-MEXICO11972
VallecitosNEW-MEXICO12018
ShivwitzUTAH12021

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