BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Gray Partridge In Great Basin

All regionsGreat BasinGeneralists

Gray Partridge in Great Basin has fallen sharply: down 58% on the route-weighted index since 1970.

-58%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 →
66Routes 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 →
55YearsYears 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 declinecomputed 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 →

Gray Partridge has fallen sharply in Great Basin: down 58% on the route-weighted index since 1970.

Gray Partridge In Great Basin Population Forecast

If the recent trend holds, Gray Partridge in Great Basin is projected to fall about 53% by 2029 — from 0.09 in 2024 to a central estimate of 0.04 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±16.8%, with 100% of held-out values landing inside the 95% band.

-53%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 →
0.04Projected 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 →
0.00–0.2195% 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 →
±16.8%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 in Great Basin is projected to fall about 53% by 2029 — from 0.09 in 2024 to a central estimate of 0.04 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±16.8%, 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 →
20250.050.000.22
20260.050.000.21
20270.050.000.21
20280.050.000.21
20290.040.000.21

Routes In Great Basin

Routes recording Gray Partridge in Great Basin.
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 →
HarringtonWASHINGTON102004
PicaboIDAHO82014
PromontoryUTAH61970
JosephOREGON42013
Moses LakeWASHINGTON42009
GiffordIDAHO32010
BakerIDAHO32019
Pasadena ValIDAHO32012
Mud LakeIDAHO32011
Lost RiverIDAHO32000
Humboldt Nf 2NEVADA32024
ConnellWASHINGTON31988
EwanWASHINGTON31995
KeystoneWASHINGTON32023
LeadoreIDAHO22018
DuboisIDAHO22010
Blacks CreekIDAHO21977
RirieIDAHO22011
PocatelloIDAHO22011
Blackft ResIDAHO22016
Iron SpringsIDAHO22024
Dougal ResIDAHO22019
Daniels ResIDAHO22007
PrestonIDAHO21988
JarbidgeNEVADA22012

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