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

Blue Grosbeak In Chihuahuan Desert

All regionsChihuahuan DesertForest birds

Blue Grosbeak in Chihuahuan Desert has surged: up 265% on the route-weighted index since 1969.

+265%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 →
57Routes 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 →

Blue Grosbeak has surged in Chihuahuan Desert: up 265% on the route-weighted index since 1969.

Blue Grosbeak In Chihuahuan Desert Population Forecast

If the recent trend holds, Blue Grosbeak in Chihuahuan Desert is projected to rise about 23% by 2030 — from 8.6 in 2025 to a central estimate of 11 (95% range 7.2–14). A 5-year backtest shows a typical error of ±24.2%, with 100% of held-out values landing inside the 95% band.

+23%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 →
11Projected 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 →
7.2–1495% 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 →
±24.2%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, Blue Grosbeak in Chihuahuan Desert is projected to rise about 23% by 2030 — from 8.6 in 2025 to a central estimate of 11 (95% range 7.2–14). A 5-year backtest shows a typical error of ±24.2%, 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 →
20269.96.613
2027106.813
2028106.914
2029107.114
2030117.214

Routes In Chihuahuan Desert

Routes recording Blue Grosbeak 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 →
LaborcitaNEW-MEXICO382019
Quitman Cyn.TEXAS352009
Quitman Canyon 2TEXAS302025
Bitter LakeNEW-MEXICO292025
PumpvilleTEXAS212025
ToyahvaleTEXAS202025
Laborcita 2NEW-MEXICO192025
Bear MtnTEXAS192025
Sierra BlancTEXAS192025
Capitan Mtn.NEW-MEXICO172017
Ozona 2TEXAS172025
San AntonioNEW-MEXICO161977
Casa PiedraTEXAS152025
Devils R CynTEXAS152025
Delaware CrkTEXAS142015
LangtryTEXAS132000
MesillaNEW-MEXICO122000
GirvinTEXAS122025
Coyanda DrawTEXAS122025
EscondidaNEW-MEXICO102025
OzonaTEXAS102022
RoswellNEW-MEXICO92025
QueenNEW-MEXICO92021
LakewoodNEW-MEXICO82021
Chisos BasinTEXAS82025

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