BirdAnalyst
Species · BCR 12 · BBS 2025 Release · 1966–2024

Magnolia Warbler In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionForest birds

Magnolia Warbler in Boreal Hardwood Transition has surged: up 603% on the route-weighted index since 1968.

+603%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 →
103Routes 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 →

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 →

Magnolia Warbler has surged in Boreal Hardwood Transition: up 603% on the route-weighted index since 1968.

Magnolia Warbler In Boreal Hardwood Transition Population Forecast

If the recent trend holds, Magnolia Warbler in Boreal Hardwood Transition is projected to rise about 65% by 2029 — from 1.9 in 2024 to a central estimate of 3.1 (95% range 2.3–3.9). A 5-year backtest shows a typical error of ±19.7%, with 80% of held-out values landing inside the 95% band.

+65%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 →
3.1Projected 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 →
2.3–3.995% 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 →
±19.7%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, Magnolia Warbler in Boreal Hardwood Transition is projected to rise about 65% by 2029 — from 1.9 in 2024 to a central estimate of 3.1 (95% range 2.3–3.9). A 5-year backtest shows a typical error of ±19.7%, 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 →
20252.92.13.8
20263.02.23.8
20273.02.23.8
20283.12.23.9
20293.12.33.9

Routes In Boreal Hardwood Transition

Routes recording Magnolia Warbler in Boreal 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 →
Sawbill LndgMINNESOTA252024
JordanMINNESOTA252023
Hart LakeMINNESOTA162024
Sawbill CampMINNESOTA132024
LockportMINNESOTA102024
Land O' Lakes 2WISCONSIN102024
IshpemingMICHIGAN82023
Land O LakesWISCONSIN82016
HermanMICHIGAN72022
HovlandMINNESOTA72024
Eagle RiverWISCONSIN72024
Gibbs CityMICHIGAN62024
EnsignMICHIGAN52010
Sherry LakeMINNESOTA52022
Crane LakeMINNESOTA52024
OntonagonMICHIGAN42019
Betchler LksMICHIGAN42024
CohassetMINNESOTA42018
BootjackMICHIGAN32023
Ned LakeMICHIGAN32024
Pine RiverMICHIGAN32018
ChisholmMINNESOTA32024
IrmaWISCONSIN32023
HollisterWISCONSIN32016
RhinelanderWISCONSIN32023

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