BirdAnalyst
Species · Idaho · BBS 2026 Release · 1966–2025

House Sparrow Population Trend in Idaho

All statesGeneralists

House Sparrow in Idaho has fallen sharply: down 68% on the route-weighted index since 1970.

-68%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 →
40Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable House Sparrow Trends in IdahoNotable 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 →

House Sparrow has fallen sharply in Idaho: down 68% on the route-weighted index since 1970.

House Sparrow Population Forecast in Idaho

If the recent trend holds, House Sparrow in Idaho is projected to fall about 96% by 2030 — from 38 in 2025 to a central estimate of 1.4 (95% range 0.00–36). A 5-year backtest shows a typical error of ±105.8%, with 80% of held-out values landing inside the 95% band.

-96%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 →
1.4Projected 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 →
0.00–3695% 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 →
±105.8%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, House Sparrow in Idaho is projected to fall about 96% by 2030 — from 38 in 2025 to a central estimate of 1.4 (95% range 0.00–36). A 5-year backtest shows a typical error of ±105.8%, with 80% of held-out values landing inside the 95% band.19682030
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 →
20264.60.0040
20273.80.0039
20283.00.0038
20292.20.0037
20301.40.0036

House Sparrow Survey Routes in Idaho

Routes recording House Sparrow in Idaho.
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 →
Mud Lake88620251988
Ririe33320251971
Pocatello21620191979
Blacks Creek20020171968
Cedar Hill16220241989
Preston9720231988
Glenns Ferry8819861968
Acequia5920121979
Picabo5020251988
Mora3820252018
Baker3420241974
Alturas3419681968
Henry2219831973
Silver City1519891989
Carey1220251993
Pasadena Val1220161987
Sunbeam1019941994
Bates820231988
Springfield720181969
Daniels Res720251988
Dubois620251972
Blackft Res520181984
Gifford520171971
Leadore520241976
Iron Springs520241988

House Sparrow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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