BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Evening Grosbeak

FringillidaeForest birdsCoccothraustes vespertinus

Evening Grosbeak has held roughly steady: up 8% on the route-weighted index since 1968.

+8%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 →
660RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Evening Grosbeak

The Evening Grosbeak (Coccothraustes vespertinus) is a North American member of the Finches (Fringillidae). In this analysis it is grouped with the forest birds.

Size
4.5–6.5 in long (11–16 cm) — a small songbird (typical for the family)
Habitat
Woodlands and forest edges, including wooded suburbs and parks.
Diet
Insects and spiders gleaned from foliage and bark, with seeds and berries in season.
Range
Recorded on 660 Breeding Bird Survey routes across 21 states, most concentrated in the Atlantic Northern Forest.
Family
Fringillidae · Forest birds

Notable Evening Grosbeak TrendsNotable 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 Evening Grosbeak. See the full index history below.

Evening Grosbeak Population Forecast

If the recent trend holds, Evening Grosbeak is projected to rise about 44% by 2029 — from 0.14 in 2024 to a central estimate of 0.20 (95% range 0.00–0.54). A 5-year backtest shows a typical error of ±68%, with 100% of held-out values landing inside the 95% band.

+44%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 →
0.20Projected 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 →
0.00–0.5495% 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 →
±68%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, Evening Grosbeak is projected to rise about 44% by 2029 — from 0.14 in 2024 to a central estimate of 0.20 (95% range 0.00–0.54). A 5-year backtest shows a typical error of ±68%, 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 →
20250.220.000.56
20260.210.000.56
20270.210.000.55
20280.200.000.55
20290.200.000.54

Where the Evening Grosbeak Is Detected

BBS routes recording Evening Grosbeak, sized by most recent count.

Evening Grosbeak Population Trend by State

Evening Grosbeak population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Arizona-89%19879
California-49%197362
Colorado+43%197556
Connecticutinsufficient datan/a1
Idaho-82%197236
Maine-86%196867
Massachusetts-17%19915
Michigan-73%196838
Minnesota-85%197024
Montana-92%197044
Nevadainsufficient datan/a2
New Hampshire-79%196822
New Mexico-43%197311
New York-83%197030
Oregon-58%197096
South Dakotainsufficient datan/a3
Utah-94%198614
Vermont-71%196821
Washington-69%197075
Wisconsin-42%197030
Wyoming-74%198014

Evening Grosbeak Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Evening Grosbeak population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Northern Pacific Rainforest-37%197099
Great Basin-79%197076
Northern Rockies-93%1970114
Boreal Hardwood Transition-75%196888
Atlantic Northern Forest-94%1968131
Sierra Nevada-64%197330
Southern Rockies / Colorado Plateau+73%197081
Badlands and Prairies-93%19819

Evening Grosbeak Conservation Status

Our route-weighted index shows it up about 8% since 1968.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.