BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Gambel's Quail

OdontophoridaeGame birdsCallipepla gambelii

Gambel's Quail has surged: up 139% on the route-weighted index since 1970.

+139%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 →
177RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
56Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Gambel's Quail

The Gambel's Quail (Callipepla gambelii) is a North American member of the New World Quail (Odontophoridae). In this analysis it is grouped with the game birds.

Size
8–11 in long (20–28 cm) — a small, round game bird (typical for the family)
Habitat
Fields, brushland, prairie and the forest floor, where it forages and nests on the ground.
Diet
Seeds, grain, buds, leaves and insects gathered on the ground.
Range
Recorded on 177 Breeding Bird Survey routes across 8 states, most concentrated in the Sonoran and Mojave Deserts.
Family
Odontophoridae · Game birds

Notable Gambel's Quail TrendsNotable 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 surveyed states: up 139% on the route-weighted index since 1970.

Gambel's Quail Population Forecast

If the recent trend holds, Gambel's Quail is projected to rise about 20% by 2029 — from 0.61 in 2024 to a central estimate of 0.73 (95% range 0.40–1.1). A 5-year backtest shows a typical error of ±26.2%, with 100% of held-out values landing inside the 95% band.

+20%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 →
0.73Projected 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 →
0.40–1.195% 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 →
±26.2%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, Gambel's Quail is projected to rise about 20% by 2029 — from 0.61 in 2024 to a central estimate of 0.73 (95% range 0.40–1.1). A 5-year backtest shows a typical error of ±26.2%, 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 →
20250.690.371.0
20260.700.381.0
20270.710.391.0
20280.720.391.0
20290.730.401.1

Where the Gambel's Quail Is Detected

BBS routes recording Gambel's Quail, sized by most recent count.

Gambel's Quail Population Trend by State

Gambel's Quail population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Arizona+44%197068
California-66%197037
Colorado+135%19929
Idahoinsufficient datan/a2
Nevada+662%19709
New Mexico+545%197035
Texas34×19948
Utah+911%19909

Gambel's Quail Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Gambel's Quail population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Great Basin+46%19707
Southern Rockies / Colorado Plateau+9%197039
Sonoran and Mojave Deserts+32%197074
Sierra Madre Occidental+15%197028
Chihuahuan Desert22×197025

Gambel's Quail Conservation Status

Our route-weighted index shows it up about 139% since 1970.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.