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Species · Indiana · BBS 2026 Release · 1966–2025

Carolina Wren Population Trend in Indiana

All statesForest birds

Carolina Wren in Indiana has surged: up 102% on the route-weighted index since 1968.

+102%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 →
64Routes 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 Carolina Wren Trends in IndianaNotable 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 Indiana: up 102% on the route-weighted index since 1968.

Carolina Wren Population Forecast in Indiana

If the recent trend holds, Carolina Wren in Indiana is projected to fall about 11% by 2030 — from 6.2 in 2025 to a central estimate of 5.5 (95% range 2.5–8.6). A 5-year backtest shows a typical error of ±29.6%, with 80% of held-out values landing inside the 95% band.

-11%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 →
5.5Projected 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 →
2.5–8.695% 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 →
±29.6%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 Indiana is projected to fall about 11% by 2030 — from 6.2 in 2025 to a central estimate of 5.5 (95% range 2.5–8.6). A 5-year backtest shows a typical error of ±29.6%, with 80% 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 →
20265.32.28.4
20275.42.38.4
20285.42.38.5
20295.52.48.5
20305.52.58.6

Carolina Wren Survey Routes in Indiana

Routes recording Carolina Wren in Indiana.
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 →
Friendswood2320241988
Belmont2120241983
Scottsburg2120251982
Witts Station1920252000
Indian Spgs1820251986
Evansville1720221966
Brookville1620251966
Georgia1620251999
Washington1520251987
Celestine1520251981
New Phila1520251982
Wallace1420242000
Newberry1420252000
Cyprss1420251999
Spencer1220241967
Clear Spring1020251981
Pimento920251984
Shelbyville920251985
Millersburg920241981
Vevay920251966
Monticello820251988
Azalia820251982
Cumback820251966
Lakeville820242024
Knox720251992

Carolina Wren Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsin

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