BirdAnalyst
Species · BCR 23 · BBS 2026 Release · 1966–2025

Nashville Warbler In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionForest birds

Nashville Warbler in Prairie Hardwood Transition has declined: down 30% on the route-weighted index since 1968.

-30%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 →
42Routes 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 →
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 SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Nashville Warbler in Prairie Hardwood Transition. See the full index history below.

Nashville Warbler In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Nashville Warbler in Prairie Hardwood Transition is projected to fall about 77% by 2030 — from 0.21 in 2025 to a central estimate of 0.05 (95% range 0.00–0.23). A 5-year backtest shows a typical error of ±57%, with 100% of held-out values landing inside the 95% band.

-77%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 →
0.05Projected 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 →
0.00–0.2395% 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 →
±57%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, Nashville Warbler in Prairie Hardwood Transition is projected to fall about 77% by 2030 — from 0.21 in 2025 to a central estimate of 0.05 (95% range 0.00–0.23). A 5-year backtest shows a typical error of ±57%, with 100% 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 →
20260.070.000.25
20270.060.000.25
20280.060.000.24
20290.050.000.24
20300.050.000.23

Routes In Prairie Hardwood Transition

Routes recording Nashville Warbler 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 →
Pigeon CreekWISCONSIN52025
Barry S.G.A. 2MICHIGAN42015
LoraineWISCONSIN42018
RemusMICHIGAN22025
HungerfordMICHIGAN22025
EvergreenMINNESOTA22025
CadottWISCONSIN22025
HatfieldWISCONSIN21998
StratfordWISCONSIN21998
Stevens PtWISCONSIN22003
ClintonvilleWISCONSIN21996
CascoWISCONSIN22008
ScottvilleMICHIGAN12025
Big Blue LkMICHIGAN12010
No BradleyMICHIGAN11994
OlaMICHIGAN12000
Maple RapidsMICHIGAN12001
OwendaleMICHIGAN11979
Chippewa Lk.MICHIGAN11996
Allegan WmaMICHIGAN12003
Barry S.G.A.MICHIGAN12012
EdwardsMINNESOTA11996
Brook ParkMINNESOTA11998
Sherburne NrMINNESOTA12025
DresserWISCONSIN12011

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