BirdAnalyst
Species · BBS 2026 Release · 1966–2025

Gray Partridge Population Analysis

PhasianidaeGame birdsPerdix perdix

Gray Partridge has surged: up 87% on the route-weighted index since 1968.

+87%Since 1968TrendPercent 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 →
319RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
59Years 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 Gray Partridge

The Gray Partridge (Perdix perdix) is a North American member of the Pheasants, Grouse & Turkeys (Phasianidae). In this analysis it is grouped with the game birds.

Size
12–47 in long (30–120 cm) — a ground-dwelling 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 319 Breeding Bird Survey routes across 16 states, most concentrated in the Prairie Potholes.
Family
Phasianidae · Game birds

Notable Gray Partridge TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Gray Partridge. See the full index history below.

Gray Partridge Population Forecast

If the recent trend holds, Gray Partridge is projected to fall about 64% by 2030 — from 0.07 in 2025 to a central estimate of 0.03 (95% range 0.00–0.10). A 5-year backtest shows a typical error of ±48.6%, with 100% of held-out values landing inside the 95% band.

-64%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 →
0.03Projected 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 →
0.00–0.1095% 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 →
±48.6%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, Gray Partridge is projected to fall about 64% by 2030 — from 0.07 in 2025 to a central estimate of 0.03 (95% range 0.00–0.10). A 5-year backtest shows a typical error of ±48.6%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.030.000.10
20270.030.000.10
20280.030.000.10
20290.030.000.10
20300.030.000.10

Where the Gray Partridge Is Detected

BBS routes recording Gray Partridge, sized by most recent count.

Gray Partridge Population Trend by State

Gray Partridge 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 →
Idaho-6%197827
Illinois-96%197111
Indianainsufficient datan/a3
Iowa+57%197027
Minnesota+7%197140
Montana+124%197055
Nebraskainsufficient datan/a5
Nevadainsufficient datan/a4
New Yorkinsufficient datan/a2
North Dakota+179%196950
Oregon-88%19789
South Dakota+29%197228
Utahinsufficient datan/a6
Washington-28%197124
Wisconsin-78%196817
Wyoming+193%199111

Gray Partridge Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Gray Partridge 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-20%197067
Northern Rockies+77%197325
Prairie Potholes+170%1969113
Badlands and Prairies+348%197048
Eastern Tallgrass Prairie-92%196934
Prairie Hardwood Transition-69%196828

Gray Partridge Conservation Status

Our route-weighted index shows it up about 87% since 1968.

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.