BirdAnalyst
Species · BCR 17 · BBS 2026 Release · 1966–2025

Black-headed Grosbeak In Badlands and Prairies

All regionsBadlands and PrairiesForest birds

Black-headed Grosbeak in Badlands and Prairies has surged: up 865% on the route-weighted index since 1969.

+865%Since 1969TrendPercent 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 →
97Routes In RegionSurvey 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 SignalsNotable 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 →

Black-headed Grosbeak has surged in Badlands and Prairies: up 865% on the route-weighted index since 1969.

Black-headed Grosbeak In Badlands and Prairies Population Forecast

If the recent trend holds, Black-headed Grosbeak in Badlands and Prairies is projected to stay roughly flat through 2030, near 1.2 (95% range 0.84–1.5). A 5-year backtest shows a typical error of ±29.1%, with 80% of held-out values landing inside the 95% band.

-8%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 →
1.2Projected 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 →
0.84–1.595% 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 →
±29.1%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, Black-headed Grosbeak in Badlands and Prairies is projected to stay roughly flat through 2030, near 1.2 (95% range 0.84–1.5). A 5-year backtest shows a typical error of ±29.1%, with 80% of held-out values landing inside the 95% band.19672030
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 →
20261.10.781.4
20271.10.791.4
20281.10.811.5
20291.10.821.5
20301.20.841.5

Routes In Badlands and Prairies

Routes recording Black-headed Grosbeak in Badlands and Prairies.
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 →
Moskee 3WYOMING142025
Reed PointMONTANA102025
HazelrodtSOUTH-DAKOTA92025
WyarnoWYOMING82025
BrandenbergMONTANA72025
SundanceWYOMING72025
SavageMONTANA62019
Long DrawSOUTH-DAKOTA62025
HighwoodMONTANA52025
CusterSOUTH-DAKOTA52025
MeadowdaleWYOMING52025
Moskee 2WYOMING52021
TobaccoNORTH-DAKOTA42019
Silver CitySOUTH-DAKOTA42012
RochfordSOUTH-DAKOTA42025
DaytonWYOMING42025
MoskeeWYOMING42001
St Xavier 2MONTANA32018
Miles CityMONTANA32024
Ft YatesNORTH-DAKOTA32004
BadlandsSOUTH-DAKOTA32003
Railroad ButteSOUTH-DAKOTA32004
Wind Cave NpSOUTH-DAKOTA32025
Chuffey SpringMONTANA22025
Bull Mtn.MONTANA22021

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