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Species · Minnesota · BBS 2026 Release · 1966–2025

Blackburnian Warbler Population Trend in Minnesota

All statesForest birds

Blackburnian Warbler in Minnesota has surged: up 189% on the route-weighted index since 1969.

+189%Since 1969TrendPercent 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 →
37Routes 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 →
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 Blackburnian 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 →

Blackburnian Warbler has surged in Minnesota: up 189% on the route-weighted index since 1969.

Blackburnian Warbler Population Forecast in Minnesota

If the recent trend holds, Blackburnian Warbler in Minnesota is projected to fall about 27% by 2030 — from 2.5 in 2025 to a central estimate of 1.8 (95% range 0.85–2.7). A 5-year backtest shows a typical error of ±30.6%, with 40% of held-out values landing inside the 95% band.

-27%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 →
1.8Projected 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 →
0.85–2.795% 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 →
±30.6%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, Blackburnian Warbler in Minnesota is projected to fall about 27% by 2030 — from 2.5 in 2025 to a central estimate of 1.8 (95% range 0.85–2.7). A 5-year backtest shows a typical error of ±30.6%, with 40% of held-out values landing inside the 95% band.19672030
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 →
20261.70.792.7
20271.70.802.7
20281.80.822.7
20291.80.842.7
20301.80.852.7

Blackburnian Warbler Survey Routes in Minnesota

Routes recording Blackburnian 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 →
Crane Lake3020251969
Sawbill Lndg2620251973
Sherry Lake1920221969
Lockport1620251967
Jordan1620251993
Sawbill Camp1320251993
Blackduck1220222004
Glendale1220251993
Hart Lake1120251968
Chisholm1120242019
Bena519771977
Nett Lake420242013
Bigfork420251993
Hovland320251973
Mahtowa320231995
Tamarac Nwr220111995
Cromwell220251967
Mille Lacs220101969
Cohasset220181973
Debs220171969
Babbitt220231994
Cass Lake120161980
Nebish120251982
Princeton119701970
Backus120251986

Blackburnian Warbler Population Trend in Other States

connecticutgeorgiaindianamainemarylandmassachusettsmichigannew-hampshirenew-jerseynew-yorknorth-carolinaohiopennsylvaniarhode-islandtennesseevermontvirginiawest-virginiawisconsin

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