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Species · Minnesota · BBS 2025 Release · 1966–2024

Black-throated Blue Warbler Population Trend in Minnesota

All statesForest birds

Black-throated Blue Warbler in Minnesota has surged: up 359% on the route-weighted index since 1972.

+359%Since 1972TrendPercent 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 →
15Routes 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 →
48YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-throated Blue 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 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 Blue Warbler has surged in Minnesota: up 359% on the route-weighted index since 1972.

Black-throated Blue Warbler Population Forecast in Minnesota

If the recent trend holds, Black-throated Blue Warbler in Minnesota is projected to rise about 21% by 2029 — from 0.07 in 2024 to a central estimate of 0.09 (95% range 0.00–0.20). A 5-year backtest shows a typical error of ±72.1%, with 40% of held-out values landing inside the 95% band.

+21%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 →
0.00–0.2095% 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 →
±72.1%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 Blue Warbler in Minnesota is projected to rise about 21% by 2029 — from 0.07 in 2024 to a central estimate of 0.09 (95% range 0.00–0.20). A 5-year backtest shows a typical error of ±72.1%, with 40% 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 →
20250.090.000.20
20260.090.000.20
20270.090.000.20
20280.090.000.20
20290.090.000.20

Black-throated Blue Warbler Survey Routes in Minnesota

Routes recording Black-throated Blue 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 →
Sawbill Camp420221993
Lockport220241967
Sawbill Lndg220242000
Bemidji219801980
Cromwell220041972
Tamarac Nwr120111991
Babbitt120222022
Debs119921981
Blackduck120192019
Cass Lake120041983
Crane Lake120221971
Nebish119891983
Lude119871981
Waskish119921992
Hovland120221974

Black-throated Blue Warbler Population Trend in Other States

connecticutgeorgiamainemarylandmassachusettsmichigannew-hampshirenew-jerseynew-yorknorth-carolinapennsylvaniarhode-islandtennesseevermontvirginiawest-virginiawisconsin

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