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Species · Indiana · BBS 2025 Release · 1966–2024

Black-throated Green Warbler Population Trend in Indiana

All statesForest birds

Black-throated Green Warbler in Indiana has surged: up 321% on the route-weighted index since 1991.

+321%Since 1991TrendPercent 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 →
5Routes 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 →
26YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-throated Green Warbler 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 →

Black-throated Green Warbler has surged in Indiana: up 321% on the route-weighted index since 1991.

Black-throated Green Warbler Population Forecast in Indiana

If the recent trend holds, Black-throated Green Warbler in Indiana is projected to rise about 57% by 2029 — from 0.09 in 2024 to a central estimate of 0.14 (95% range 0.02–0.27). A 5-year backtest shows a typical error of ±23.4%, with 100% of held-out values landing inside the 95% band.

+57%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 →
0.14Projected 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 →
0.02–0.2795% 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 →
±23.4%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, Black-throated Green Warbler in Indiana is projected to rise about 57% by 2029 — from 0.09 in 2024 to a central estimate of 0.14 (95% range 0.02–0.27). A 5-year backtest shows a typical error of ±23.4%, with 100% of held-out values landing inside the 95% band.19882029
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 →
20250.130.010.26
20260.140.010.26
20270.140.010.27
20280.140.010.27
20290.140.020.27

Black-throated Green Warbler Survey Routes in Indiana

Routes recording Black-throated Green Warbler 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 →
Hoosier520241990
Indiana Dune320031998
Belmont220221988
Clear Spring120042004
Lagrange120012001

Black-throated Green Warbler Population Trend in Other States

alabamaarkansasconnecticutgeorgiakentuckymainemarylandmassachusettsmichiganminnesotamissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseevermontvirginiawest-virginiawisconsin

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