BirdAnalyst
Species · BCR 23 · BBS 2025 Release · 1966–2024

Mourning Warbler In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionForest birds

Mourning Warbler in Prairie Hardwood Transition has declined: down 39% on the route-weighted index since 1968.

-39%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 →
72Routes 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 →
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 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 Mourning Warbler in Prairie Hardwood Transition. See the full index history below.

Mourning Warbler In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Mourning Warbler in Prairie Hardwood Transition is projected to rise about 139% by 2029 — from 0.14 in 2024 to a central estimate of 0.33 (95% range 0.05–0.61). A 5-year backtest shows a typical error of ±226.4%, with 40% of held-out values landing inside the 95% band.

+139%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 →
0.33Projected 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 →
0.05–0.6195% 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 →
±226.4%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, Mourning Warbler in Prairie Hardwood Transition is projected to rise about 139% by 2029 — from 0.14 in 2024 to a central estimate of 0.33 (95% range 0.05–0.61). A 5-year backtest shows a typical error of ±226.4%, with 40% 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 →
20250.330.050.61
20260.330.050.61
20270.330.050.61
20280.330.050.61
20290.330.050.61

Routes In Prairie Hardwood Transition

Routes recording Mourning 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 →
CumberlandWISCONSIN32018
CadottWISCONSIN32019
HatfieldWISCONSIN31979
Wis RapidsWISCONSIN32015
Stevens PtWISCONSIN32023
ScottvilleMICHIGAN22023
No BradleyMICHIGAN22015
Allegan WmaMICHIGAN22002
Barry S.G.A.MICHIGAN22012
Barry S.G.A. 2MICHIGAN22019
EvergreenMINNESOTA22016
HolwayWISCONSIN21989
MerrillWISCONSIN22024
StratfordWISCONSIN22011
SaxevilleWISCONSIN22024
Oconto FallsWISCONSIN22023
OmroWISCONSIN22001
ClintonvilleWISCONSIN22012
New LisbonWISCONSIN22015
PrincetonWISCONSIN22005
Pt WashingtnWISCONSIN22024
GreshamWISCONSIN22024
GrimmsWISCONSIN22013
PackertownINDIANA11993
Big Blue LkMICHIGAN12014

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