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Species · Texas · BBS 2025 Release · 1966–2024

Bell's Vireo Population Trend in Texas

All statesForest birds

Bell's Vireo in Texas has surged: up 132% on the route-weighted index since 1969.

+132%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 →
140Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Bell's Vireo Trends in TexasNotable 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 Texas: up 132% on the route-weighted index since 1969.

Bell's Vireo Population Forecast in Texas

If the recent trend holds, Bell's Vireo in Texas is projected to stay roughly flat through 2029, near 4.0 (95% range 2.7–5.2). A 5-year backtest shows a typical error of ±21.3%, with 60% of held-out values landing inside the 95% band.

+5%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 →
4.0Projected 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 →
2.7–5.295% 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 →
±21.3%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 Texas is projected to stay roughly flat through 2029, near 4.0 (95% range 2.7–5.2). A 5-year backtest shows a typical error of ±21.3%, with 60% of held-out values landing inside the 95% band.19672029
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 →
20253.82.55.0
20263.82.65.1
20273.92.65.1
20283.92.75.2
20294.02.75.2

Bell's Vireo Survey Routes in Texas

Routes recording Bell's Vireo in Texas.
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 →
San Saba5320241969
Harper4520241969
Montell4420241995
Valley Spgs4120241968
Eldorado4120231986
Longfellow3920241968
Ozona3720221975
Rockspring3620241994
Comstock3520231967
Pear Valley3220241969
Devils R Cyn2520241994
Albany2420241969
Allen Creek2420241994
Mertzon2020191967
Indian Mtn1920241976
Pumpville1920242006
Mertzon 21820242022
Dove Mtn.1620062003
Prairie Mtn.1520241994
La Pryor1420091969
Winchell1420241969
Utopia1320241969
Casa Piedra1320231986
Quitman Cyn.1320091999
Silver1320242003

Bell's Vireo Population Trend in Other States

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