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Species · Minnesota · BBS 2025 Release · 1966–2024

Bay-breasted Warbler Population Trend in Minnesota

All statesForest birds

Bay-breasted Warbler in Minnesota has fallen sharply: down 56% on the route-weighted index since 1976.

-56%Since 1976TrendPercent 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 →
13Routes 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 →
34YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Bay-breasted Warbler Trends in MinnesotaNotable 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 declinecomputed 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 →

Bay-breasted Warbler has fallen sharply in Minnesota: down 56% on the route-weighted index since 1976.

Bay-breasted Warbler Population Forecast in Minnesota

If the recent trend holds, Bay-breasted Warbler in Minnesota is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±44.8%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.02Projected 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 →
0.00–0.0895% 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 →
±44.8%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, Bay-breasted Warbler in Minnesota is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±44.8%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.020.000.09
20260.020.000.09
20270.020.000.09
20280.020.000.09
20290.020.000.08

Bay-breasted Warbler Survey Routes in Minnesota

Routes recording Bay-breasted Warbler in Minnesota.
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 →
Waskish319821982
Cohasset220121989
Crane Lake220242024
Lockport120111967
Sawbill Lndg120211979
Hart Lake119911975
Sawbill Camp120211998
Jordan120212013
Babbitt120212017
Cass Lake119831983
Nebish120141986
Red Lake120061996
Nett Lake120152015

Bay-breasted Warbler Population Trend in Other States

mainemichigannew-hampshirenew-yorkpennsylvaniavermontwisconsin

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