BirdAnalyst
Species · BCR 35 · BBS 2026 Release · 1966–2025

Bell's Vireo In Chihuahuan Desert

All regionsChihuahuan DesertForest birds

Bell's Vireo in Chihuahuan Desert has surged: up 206% on the route-weighted index since 1969.

+206%Since 1969TrendPercent 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 →
43Routes 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 →
58YearsYears 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 →

Bell's Vireo has surged in Chihuahuan Desert: up 206% on the route-weighted index since 1969.

Bell's Vireo In Chihuahuan Desert Population Forecast

If the recent trend holds, Bell's Vireo in Chihuahuan Desert is projected to stay roughly flat through 2030, near 7.3 (95% range 5.3–9.2). A 5-year backtest shows a typical error of ±18.1%, with 100% of held-out values landing inside the 95% band.

-3%Change by 2030TrendPercent 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 →
7.3Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
5.3–9.295% 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 →
±18.1%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, Bell's Vireo in Chihuahuan Desert is projected to stay roughly flat through 2030, near 7.3 (95% range 5.3–9.2). A 5-year backtest shows a typical error of ±18.1%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20266.94.98.8
20277.05.08.9
20287.15.19.0
20297.25.29.1
20307.35.39.2

Routes In Chihuahuan Desert

Routes recording Bell's Vireo 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 →
Ozona 2TEXAS402025
OzonaTEXAS372022
Devils R CynTEXAS352025
LongfellowTEXAS282025
Red RockNEW-MEXICO202025
ToyahvaleTEXAS202025
Sierra BlancTEXAS202025
ComstockTEXAS192025
Dove Mtn.TEXAS162006
PumpvilleTEXAS152025
Bear MtnTEXAS142025
Quitman Cyn.TEXAS132009
CastolonTEXAS122025
LangtryTEXAS112000
Casa PiedraTEXAS92025
AltudaTEXAS72023
Coyanda DrawTEXAS72025
ShafterTEXAS51985
MarathonTEXAS52025
Ft. DavisTEXAS52023
LaborcitaNEW-MEXICO42019
Black GapTEXAS42025
ColumbusNEW-MEXICO32024
Laborcita 2NEW-MEXICO32025
Delaware CrkTEXAS32015

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.