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Species · Michigan · BBS 2026 Release · 1966–2025

Philadelphia Vireo Population Trend in Michigan

All statesForest birds

Philadelphia Vireo in Michigan has surged: up 131% on the route-weighted index since 1993.

+131%Since 1993TrendPercent 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 →
12Routes 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 →
19YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Philadelphia Vireo 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 →

No notable trend signals for Philadelphia Vireo in Michigan. See the full index history below.

Philadelphia Vireo Population Forecast in Michigan

If the recent trend holds, Philadelphia Vireo in Michigan is projected to stay roughly flat through 2027, near 0.07 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±55.9%, with 80% of held-out values landing inside the 95% band.

n/aChange by 2027TrendPercent 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 →
0.07Projected 2027 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1495% 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 →
±55.9%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, Philadelphia Vireo in Michigan is projected to stay roughly flat through 2027, near 0.07 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±55.9%, with 80% of held-out values landing inside the 95% band.19882027
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 →
20230.070.000.14
20240.070.000.14
20250.070.000.14
20260.070.000.14
20270.070.000.14

Philadelphia Vireo Survey Routes in Michigan

Routes recording Philadelphia Vireo 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 →
Ontonagon420192012
Ishpeming420191990
Crystal Fls319881988
Bergland220222009
Imp Lake220122000
Herman120132013
Hiawatha Nf119941994
Pickford120112011
Sidnaw120131996
Cunard120161990
Cluster Lakes120072007
Lake City120012001

Philadelphia Vireo Population Trend in Other States

alabamamaineminnesotanew-hampshirenew-yorknorth-dakotavermontwisconsin

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