BirdAnalyst
Species · BCR 23 · BBS 2025 Release · 1966–2024

Carolina Wren In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionForest birds

Carolina Wren in Prairie Hardwood Transition has surged: up 22× on the route-weighted index since 1973.

22×Since 1973TrendPercent 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 →
51Routes 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 →
44YearsYears 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 Prairie Hardwood Transition: up 22× on the route-weighted index since 1973.

Carolina Wren In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Carolina Wren in Prairie Hardwood Transition is projected to fall about 64% by 2029 — from 0.54 in 2024 to a central estimate of 0.19 (95% range 0.04–0.34). A 5-year backtest shows a typical error of ±59%, with 20% of held-out values landing inside the 95% band.

-64%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 →
0.04–0.3495% 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 →
±59%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 Prairie Hardwood Transition is projected to fall about 64% by 2029 — from 0.54 in 2024 to a central estimate of 0.19 (95% range 0.04–0.34). A 5-year backtest shows a typical error of ±59%, with 20% of held-out values landing inside the 95% band.19662029
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 →
20250.180.030.33
20260.180.030.33
20270.180.030.34
20280.190.040.34
20290.190.040.34

Routes In Prairie Hardwood Transition

Routes recording Carolina Wren in Prairie Hardwood Transition.
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 →
LakevilleINDIANA82024
KnoxINDIANA62024
PackertownINDIANA61993
HomerMICHIGAN62024
LagrangeINDIANA52024
GalesburgMICHIGAN52024
MottvilleMICHIGAN42024
Belding 2MICHIGAN42024
KewannaINDIANA32022
MiddleburyINDIANA32024
NashvilleMICHIGAN32024
Bell OakMICHIGAN32005
EllisINDIANA22023
Packertown 2INDIANA22024
DeckervilleMICHIGAN22013
KingswayOHIO22024
Columbia CtyINDIANA12022
Indiana DuneINDIANA12008
ScottvilleMICHIGAN12019
Big Blue LkMICHIGAN12024
LawrenceMICHIGAN12024
New TroyMICHIGAN12022
HowardsvilleMICHIGAN12022
MontereyMICHIGAN12004
OlaMICHIGAN12018

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