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Species · Michigan · BBS 2026 Release · 1966–2025

Nashville Warbler Population Trend in Michigan

All statesForest birds

Nashville Warbler in Michigan has surged: up 717% on the route-weighted index since 1968.

+717%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 →
67Routes 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 Nashville Warbler Trends in MichiganNotable 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 →

Nashville Warbler has surged in Michigan: up 717% on the route-weighted index since 1968.

Nashville Warbler Population Forecast in Michigan

If the recent trend holds, Nashville Warbler in Michigan is projected to stay roughly flat through 2030, near 10 (95% range 6.8–13). A 5-year backtest shows a typical error of ±29.5%, with 80% of held-out values landing inside the 95% band.

+5%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 →
10Projected 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 →
6.8–1395% 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 →
±29.5%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, Nashville Warbler in Michigan is projected to stay roughly flat through 2030, near 10 (95% range 6.8–13). A 5-year backtest shows a typical error of ±29.5%, with 80% 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 →
20269.56.313
20279.66.413
20289.76.613
20299.96.713
2030106.813

Nashville Warbler Survey Routes in Michigan

Routes recording Nashville Warbler in Michigan.
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 →
Brocky Lake6820251980
Ishpeming4920251980
Betchler Lks4820251992
Gibbs City4220251979
Muskallonge3120241966
Ontonagon2920191967
Sidnaw2820251993
Brush Creek2320161975
Crystal Fls2020251985
Seney Nwr2020251992
Ned Lake1920251986
Imp Lake1920191992
Tahquamenon1820251974
Hubbard Lake1819961975
Ensign1820102006
Bergland1720221979
Maple Grove1720251969
Cluster Lakes1720102006
Herman1520221983
Wilson1520101975
Raco1520251971
Isabella 21420252013
Gooseneck1320102008
Shingleton1220251967
Isabella1220091966

Nashville Warbler Population Trend in Other States

californiaconnecticutidahomainemarylandmassachusettsminnesotamontananew-hampshirenew-jerseynew-yorknorth-dakotaoregonpennsylvaniarhode-islandvermontvirginiawashingtonwest-virginiawisconsin

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