BirdAnalyst
Species · BCR 14 · BBS 2025 Release · 1966–2024

Carolina Wren In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Carolina Wren in Atlantic Northern Forest has surged: up 27× on the route-weighted index since 1976.

27×Since 1976TrendPercent 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 RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
28YearsYears 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 →

Carolina Wren has surged in Atlantic Northern Forest: up 27× on the route-weighted index since 1976.

Carolina Wren In Atlantic Northern Forest Population Forecast

If the recent trend holds, Carolina Wren in Atlantic Northern Forest is projected to fall about 71% by 2029 — from 0.66 in 2024 to a central estimate of 0.19 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±88.4%, with 20% of held-out values landing inside the 95% band.

-71%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 →
0.19Projected 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 →
0.00–0.4295% 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 →
±88.4%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, Carolina Wren in Atlantic Northern Forest is projected to fall about 71% by 2029 — from 0.66 in 2024 to a central estimate of 0.19 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±88.4%, with 20% of held-out values landing inside the 95% band.19742029
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 →
20250.170.000.41
20260.180.000.41
20270.180.000.41
20280.190.000.42
20290.190.000.42

Routes In Atlantic Northern Forest

Routes recording Carolina Wren in Atlantic Northern Forest.
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 →
New HartfordCONNECTICUT72024
MontereyMASSACHUSETTS72024
SheffieldMASSACHUSETTS52022
FitzwilliamNEW-HAMPSHIRE52024
PeterboroughNEW-HAMPSHIRE42024
ConcordNEW-HAMPSHIRE42024
N OrangeMASSACHUSETTS32024
ChesterfieldMASSACHUSETTS32024
Northfield 2MAINE22014
CanterburyNEW-HAMPSHIRE22022
W RutlandVERMONT22024
New HartfordCONNECTICUT11978
WestbrookMAINE12024
Otisfield GrMAINE12012
HartfordMAINE12014
Bowdoin CtrMAINE12013
FreedomMAINE12021
CarrabassettMAINE12017
CummingtonMASSACHUSETTS12012
Cummington 2MASSACHUSETTS12024
HopkintonNEW-HAMPSHIRE12024
Gilmantn I WNEW-HAMPSHIRE12021
WalpoleNEW-HAMPSHIRE12022
MarlowNEW-HAMPSHIRE12024
MilanNEW-HAMPSHIRE11992

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