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

Northern House Wren Population Trend in Colorado

All statesForest birds

Northern House Wren in Colorado has risen sharply: up 67% on the route-weighted index since 1970.

+67%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 →
133Routes 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 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 67% 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 33% by 2030 — from 4.5 in 2025 to a central estimate of 6.0 (95% range 4.0–8.0). A 5-year backtest shows a typical error of ±25%, with 100% of held-out values landing inside the 95% band.

+33%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 →
6.0Projected 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 →
4.0–8.095% 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 →
±25%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 33% by 2030 — from 4.5 in 2025 to a central estimate of 6.0 (95% range 4.0–8.0). A 5-year backtest shows a typical error of ±25%, with 100% 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 →
20265.83.87.8
20275.83.97.8
20285.93.97.9
20295.94.07.9
20306.04.08.0

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
Deadman Rd.3320251992
Gold Hill 22520252018
Uncompahgre1920251988
Flattops1920251992
Arsenal1920151991
Arsenal 21920252016
Tarryall1720251988
Gold Hill1720121998
Parlin1620251968
Aspen1520251979
Pagosa Spgs1519821969
Blackhead Pk1420251991
Cokedale1420251995
Douglas Pass1320241985
Owl Creek Pass1320251998
Cheesman Lk1220251969
Wet Mtns.1220251993
Comanche Pk1220241994
Baxter Pass1220241998
Dolores Riv1120251988
Steamboat L.1120251996
Buford1020251975
Colona1020141972
Thomasville1020251992

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 2026-08-14.