BirdAnalyst
Species · Michigan · BBS 2025 Release · 1966–2024

Bobolink Population Trend in Michigan

All statesGrassland birds

Bobolink in Michigan has collapsed: down 82% on the route-weighted index since 1968.

-82%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 →
93Routes 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 Bobolink 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 declinecomputed 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 →

Bobolink has collapsed in Michigan: down 82% on the route-weighted index since 1968.

Bobolink Population Forecast in Michigan

If the recent trend holds, Bobolink in Michigan is projected to fall about 100% by 2029 — from 2.4 in 2024 to a central estimate of 0.00 (95% range 0.00–3.6). A 5-year backtest shows a typical error of ±60.2%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–3.695% 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 →
±60.2%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, Bobolink in Michigan is projected to fall about 100% by 2029 — from 2.4 in 2024 to a central estimate of 0.00 (95% range 0.00–3.6). A 5-year backtest shows a typical error of ±60.2%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20250.320.003.9
20260.070.003.6
20270.000.003.6
20280.000.003.6
20290.000.003.6

Bobolink Survey Routes in Michigan

Routes recording Bobolink 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 →
Pickford6020241973
Ontonagon1620191967
Lake City1520151970
Hungerford1520241991
Pleasant Val1219971967
Ola1220241974
Hubbard Lake1219961973
Cunard1120211973
Big Rapids1119901967
Cathro1120161967
Tyre1019961967
Herron1020162011
Pettysville919791969
Riggsville820191967
Drayton Plns819871973
Allegan Wma820191993
Maple Rapids720191987
Skegemog Pt620141974
Frederic620031971
S Lyons619921968
Adrian520171966
Pleasant Valley 2520242004
Richmond520171999
New Buffalo420131994
Muskallonge320071966

Bobolink Population Trend in Other States

californiacoloradoconnecticutidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-dakotautahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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