BirdAnalyst
Species · Colorado · BBS 2025 Release · 1966–2024

Northern House Wren Population Trend in Colorado

All statesForest birds

Northern House Wren in Colorado has risen sharply: up 69% on the route-weighted index since 1970.

+69%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 →
130Routes 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 →
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 Northern House Wren Trends in ColoradoNotable 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 →

Northern House Wren has risen sharply in Colorado: up 69% on the route-weighted index since 1970.

Northern House Wren Population Forecast in Colorado

If the recent trend holds, Northern House Wren in Colorado is projected to rise about 20% by 2029 — from 5.1 in 2024 to a central estimate of 6.0 (95% range 4.1–8.0). A 5-year backtest shows a typical error of ±18.4%, 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 →
6.0Projected 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 →
4.1–8.095% 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 →
±18.4%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, Northern House Wren in Colorado is projected to rise about 20% by 2029 — from 5.1 in 2024 to a central estimate of 6.0 (95% range 4.1–8.0). A 5-year backtest shows a typical error of ±18.4%, 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 →
20255.83.97.8
20265.93.97.9
20275.94.07.9
20286.04.08.0
20296.04.18.0

Northern House Wren Survey Routes in Colorado

Routes recording Northern House Wren in Colorado.
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 →
Yampa3520231971
Ragged Mtn.3520191994
Uncompahgre3420241988
Deadman Rd.3120241992
Groundhog Rs3120241992
Owl Creek Pass2620241998
Flattops2320191992
Thomasville1920181992
Arsenal1920151991
Arsenal 21920242016
Dunckley Pas1820241992
Buford1720241975
Gold Hill1720121998
Elbert1720241998
Pagosa Spgs1519821969
Fox Creek1520241993
Yellowjacket Pass1520241998
Aspen1420241979
Parlin1420231968
Buffalo Park1420231992
Douglas Pass1320241985
Steamboat L.1320241996
Comanche Pk1220241994
Baxter Pass1220241998
Mesaverde Np1120241996

Northern House Wren Population Trend in Other States

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

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