BirdAnalyst
Species · BCR 35 · BBS 2025 Release · 1966–2024

Summer Tanager In Chihuahuan Desert

All regionsChihuahuan DesertGeneralists

Summer Tanager in Chihuahuan Desert has surged: up 186% on the route-weighted index since 1970.

+186%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 →
32Routes 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 →
51YearsYears 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 →

Summer Tanager has surged in Chihuahuan Desert: up 185% on the route-weighted index since 1970.

Summer Tanager In Chihuahuan Desert Population Forecast

If the recent trend holds, Summer Tanager in Chihuahuan Desert is projected to rise about 77% by 2029 — from 0.52 in 2024 to a central estimate of 0.91 (95% range 0.40–1.4). A 5-year backtest shows a typical error of ±72.9%, with 100% of held-out values landing inside the 95% band.

+77%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 →
0.91Projected 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 →
0.40–1.495% 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 →
±72.9%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 Chihuahuan Desert is projected to rise about 77% by 2029 — from 0.52 in 2024 to a central estimate of 0.91 (95% range 0.40–1.4). A 5-year backtest shows a typical error of ±72.9%, 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 →
20250.860.351.4
20260.880.361.4
20270.890.381.4
20280.900.391.4
20290.910.401.4

Routes In Chihuahuan Desert

Routes recording Summer Tanager in Chihuahuan Desert.
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 →
Quitman Cyn.TEXAS122009
Red RockNEW-MEXICO42024
MesillaNEW-MEXICO42000
Bear MtnTEXAS42012
ToyahvaleTEXAS42024
Devils R CynTEXAS32024
LaborcitaNEW-MEXICO22019
QueenNEW-MEXICO22019
Hot SpringsTEXAS22001
OzonaTEXAS22022
Casa PiedraTEXAS22023
MarathonTEXAS22023
Quitman Canyon 2TEXAS22024
DemingNEW-MEXICO11969
EscondidaNEW-MEXICO12018
Lake ValleyNEW-MEXICO12023
Laborcita 2NEW-MEXICO12022
ComstockTEXAS12023
Black GapTEXAS12018
ShafterTEXAS11982
LongfellowTEXAS12024
AltudaTEXAS12008
ValentineTEXAS11986
Delaware CrkTEXAS12015
SlaughterTEXAS12014

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