BirdAnalyst
Species · BCR 24 · BBS 2025 Release · 1966–2024

Black-throated Green Warbler In Central Hardwoods

All regionsCentral HardwoodsForest birds

Black-throated Green Warbler in Central Hardwoods has surged: up 493% on the route-weighted index since 1991.

+493%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 →
8Routes 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 →
32YearsYears 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 →

Black-throated Green Warbler has surged in Central Hardwoods: up 493% on the route-weighted index since 1991.

Black-throated Green Warbler In Central Hardwoods Population Forecast

If the recent trend holds, Black-throated Green Warbler in Central Hardwoods is projected to rise about 15% by 2029 — from 0.08 in 2024 to a central estimate of 0.09 (95% range 0.04–0.14). A 5-year backtest shows a typical error of ±35.6%, with 100% of held-out values landing inside the 95% band.

+15%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 →
0.09Projected 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 →
0.04–0.1495% 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 →
±35.6%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, Black-throated Green Warbler in Central Hardwoods is projected to rise about 15% by 2029 — from 0.08 in 2024 to a central estimate of 0.09 (95% range 0.04–0.14). A 5-year backtest shows a typical error of ±35.6%, 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 →
20250.080.030.13
20260.090.030.14
20270.090.040.14
20280.090.040.14
20290.090.040.14

Routes In Central Hardwoods

Routes recording Black-throated Green Warbler in Central Hardwoods.
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 →
HoosierINDIANA52024
Ozark NfARKANSAS22024
BelmontINDIANA22022
FultonARKANSAS11999
RudyARKANSAS12021
Boston Mtn.ARKANSAS12024
Clear SpringINDIANA12004
Peace ValleyMISSOURI11993

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