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

Blue Grosbeak Population Trend in Ohio

All statesGeneralists

Blue Grosbeak in Ohio has surged: up 15× on the route-weighted index since 1985.

15×Since 1985TrendPercent 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 →
16Routes 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 →
40YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Blue Grosbeak Trends in OhioNotable 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 →

Blue Grosbeak has surged in Ohio: up 15× on the route-weighted index since 1985.

Blue Grosbeak Population Forecast in Ohio

If the recent trend holds, Blue Grosbeak in Ohio is projected to fall about 33% by 2029 — from 0.60 in 2024 to a central estimate of 0.41 (95% range 0.25–0.56). A 5-year backtest shows a typical error of ±27.7%, with 80% of held-out values landing inside the 95% band.

-33%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 →
0.41Projected 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 →
0.25–0.5695% 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 →
±27.7%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, Blue Grosbeak in Ohio is projected to fall about 33% by 2029 — from 0.60 in 2024 to a central estimate of 0.41 (95% range 0.25–0.56). A 5-year backtest shows a typical error of ±27.7%, with 80% of held-out values landing inside the 95% band.19722029
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 →
20250.370.220.52
20260.380.230.53
20270.390.240.54
20280.400.240.55
20290.410.250.56

Blue Grosbeak Survey Routes in Ohio

Routes recording Blue Grosbeak in Ohio.
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 →
Omega1320241972
Rome620241991
Harveysburg 2220242024
Enon220242013
Baxter Ridge220232023
Dresden220222013
Wilgus220091997
Ash Ridge220211992
Scioto Furn220132008
Kenton119911991
Kunkle120172017
Tar Hollow120182018
Bismark119861985
Botkins120142014
Darrtown120212018
Harveysburg119891989

Blue Grosbeak Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradodelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamarylandminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaoklahomapennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvirginiawest-virginiawyoming

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