BirdAnalyst
Species · Texas · BBS 2025 Release · 1966–2024

Gambel's Quail Population Trend in Texas

All statesArid-land birds

Gambel's Quail in Texas has surged: up 34× on the route-weighted index since 1994.

34×Since 1994TrendPercent 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 →
8Routes 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 →
32YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Gambel's Quail 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 →

Gambel's Quail has surged in Texas: up 34× on the route-weighted index since 1994.

Gambel's Quail Population Forecast in Texas

If the recent trend holds, Gambel's Quail in Texas is projected to rise about 237% by 2029 — from 0.38 in 2024 to a central estimate of 1.3 (95% range 0.72–1.9). A 5-year backtest shows a typical error of ±55.3%, with 80% of held-out values landing inside the 95% band.

+237%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 →
1.3Projected 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 →
0.72–1.995% 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 →
±55.3%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, Gambel's Quail in Texas is projected to rise about 237% by 2029 — from 0.38 in 2024 to a central estimate of 1.3 (95% range 0.72–1.9). A 5-year backtest shows a typical error of ±55.3%, with 80% of held-out values landing inside the 95% band.19782029
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 →
20251.20.581.7
20261.20.621.8
20271.20.651.8
20281.30.691.8
20291.30.721.9

Gambel's Quail Survey Routes in Texas

Routes recording Gambel's Quail 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 →
Presidio10120232004
Quitman Cyn.3520091999
Quitman Canyon 22620242010
Van Horn1720242017
Slaughter1620141978
Canutillo1020241994
Sierra Blanc620241999
Casa Piedra220232022

Gambel's Quail Population Trend in Other States

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