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Species · Indiana · BBS 2025 Release · 1966–2024

Carolina Wren Population Trend in Indiana

All statesForest birds

Carolina Wren in Indiana has surged: up 85% on the route-weighted index since 1968.

+85%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 →
58YearsYears 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 85% 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 35% by 2029 — from 8.4 in 2024 to a central estimate of 5.4 (95% range 2.3–8.5). A 5-year backtest shows a typical error of ±31.7%, with 80% of held-out values landing inside the 95% band.

-35%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 →
5.4Projected 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 →
2.3–8.595% 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 →
±31.7%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 35% by 2029 — from 8.4 in 2024 to a central estimate of 5.4 (95% range 2.3–8.5). A 5-year backtest shows a typical error of ±31.7%, with 80% 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 →
20255.22.18.3
20265.22.18.3
20275.32.28.4
20285.32.38.4
20295.42.38.5

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 →
Celestine3120241981
Scottsburg3120241982
Georgia2620241999
Indian Spgs2420241986
Friendswood2320241988
Belmont2120241983
Clear Spring1920241981
Washington1820241987
New Phila1820241982
Evansville1720221966
Pimento1520241984
Azalia1520241982
Corydon1520241966
Newberry1520242000
Cyprss1520241999
Brookville1420241966
Wallace1420242000
Spencer1220241967
Monticello1120241988
Vevay1120241966
Witts Station1120242000
Brazil920241966
Millersburg920241981
Middletown820241966
Lakeville820242024

Carolina Wren Population Trend in Other States

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

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