BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

House Sparrow In Northern Rockies

All regionsNorthern RockiesGeneralists

House Sparrow in Northern Rockies has risen sharply: up 51% on the route-weighted index since 1970.

+51%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 →
107Routes 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 →
56YearsYears 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 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 →

House Sparrow has risen sharply in Northern Rockies: up 51% on the route-weighted index since 1970.

Forecast

If the recent trend holds, House Sparrow in Northern Rockies is projected to fall about 33% by 2029 — from 5.8 in 2024 to a central estimate of 3.9 (95% range 0.49–7.3). A 5-year backtest shows a typical error of ±43.7%, with 80% of held-out values landing inside the 95% band.

-33%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 →
3.9Projected 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 →
0.49–7.395% 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 →
±43.7%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 Northern Rockies is projected to fall about 33% by 2029 — from 5.8 in 2024 to a central estimate of 3.9 (95% range 0.49–7.3). A 5-year backtest shows a typical error of ±43.7%, with 80% 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 →
20253.90.547.3
20263.90.537.3
20273.90.527.3
20283.90.507.3
20293.90.497.3

Routes In Northern Rockies

Routes recording House Sparrow in Northern Rockies.
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 →
MidvaleWYOMING1272024
Pablo Res.MONTANA1142024
VictorMONTANA872024
PolsonMONTANA442024
BasinWYOMING432024
Church HillMONTANA402024
CodyWYOMING402024
AlturasIDAHO341968
GlenMONTANA322024
FrannieWYOMING312024
Elk HornWYOMING302018
Willow CreekMONTANA251981
Clyde ParkMONTANA252024
Carter 2WYOMING252024
Willow Creek 2MONTANA232024
Twin BridgesMONTANA191976
HarmonyWYOMING172023
BoulderMONTANA142024
SpartaOREGON142001
OttoWYOMING132024
MckinnonWYOMING131983
LaurelMONTANA122022
DuboisWYOMING121991
ClarkWYOMING122010
ArleeMONTANA111987

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