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Species · Wisconsin · BBS 2026 Release · 1966–2025

Blackburnian Warbler Population Trend in Wisconsin

All statesForest birds

Blackburnian Warbler in Wisconsin has surged: up 134% on the route-weighted index since 1968.

+134%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 →
38Routes 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 →
59YearsYears 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 WisconsinNotable 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 Wisconsin: up 134% on the route-weighted index since 1968.

Blackburnian Warbler Population Forecast in Wisconsin

If the recent trend holds, Blackburnian Warbler in Wisconsin is projected to stay roughly flat through 2030, near 0.93 (95% range 0.55–1.3). A 5-year backtest shows a typical error of ±25%, with 60% of held-out values landing inside the 95% band.

-0%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 →
0.93Projected 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 →
0.55–1.395% 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 →
±25%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 Wisconsin is projected to stay roughly flat through 2030, near 0.93 (95% range 0.55–1.3). A 5-year backtest shows a typical error of ±25%, with 60% of held-out values landing inside the 95% band.19662030
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 →
20260.890.511.3
20270.900.521.3
20280.910.531.3
20290.920.541.3
20300.930.551.3

Blackburnian Warbler Survey Routes in Wisconsin

Routes recording Blackburnian Warbler in Wisconsin.
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 →
Eagle River1520251966
Land O Lakes1020161967
Shanagolden920251966
Land O' Lakes 2720252017
Grand View620251966
Popple River620251967
Cavour620251998
Pigeon Creek520192007
Rib Lake420251970
Mcnaughton420241967
Mellen420251998
Bayfield320251973
Crandon320251967
Wausaukee320221981
Washington I320241967
Montreal220241975
Exeland220251969
Irma220251969
Gresham220251999
Chaffey120211966
Iron River120251967
Minong120191974
Union Twp120131975
Loraine120151995
Cumberland120092009

Blackburnian Warbler Population Trend in Other States

connecticutgeorgiaindianamainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-carolinaohiopennsylvaniarhode-islandtennesseevermontvirginiawest-virginia

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