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

Northern House Wren Population Trend in Massachusetts

All statesForest birds

Northern House Wren in Massachusetts has risen sharply: up 52% on the route-weighted index since 1968.

+52%Since 1968TrendPercent 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 →
32Routes 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 →
59YearsYears 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 MassachusettsNotable 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 Massachusetts: up 52% on the route-weighted index since 1968.

Northern House Wren Population Forecast in Massachusetts

If the recent trend holds, Northern House Wren in Massachusetts is projected to fall about 14% by 2030 — from 11 in 2025 to a central estimate of 9.2 (95% range 4.9–13). A 5-year backtest shows a typical error of ±37.1%, with 40% of held-out values landing inside the 95% band.

-14%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 →
9.2Projected 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 →
4.9–1395% 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 →
±37.1%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 Massachusetts is projected to fall about 14% by 2030 — from 11 in 2025 to a central estimate of 9.2 (95% range 4.9–13). A 5-year backtest shows a typical error of ±37.1%, with 40% of held-out values landing inside the 95% band.19662030
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 →
20269.24.913
20279.24.913
20289.24.913
20299.24.913
20309.24.913

Northern House Wren Survey Routes in Massachusetts

Routes recording Northern House Wren in Massachusetts.
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 →
Brockton3820191967
Belchertown2520251967
Prattville2220191966
Maynard1920251967
Marion1820251966
Princeton1619761969
Mansfield1420251968
Sheffield1420221969
Holden1420251977
Pittsfield1120161967
Monterey1120252019
Warren 21120252010
Newburyport1020221967
E Pepperell1019941966
Warren1020091968
S Barre1020251968
Chesterfield1020251967
N Oxford920251968
N Orange920251968
N. Andover820251997
E Dennis620211967
Wellfleet 2520252016
Cummington 2520252015
Cummington320141968
Hancock320151997

Northern House Wren Population Trend in Other States

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

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