BirdAnalyst
Species · BCR 11 · BBS 2026 Release · 1966–2025

Blue Grosbeak In Prairie Potholes

All regionsPrairie PotholesForest birds

Blue Grosbeak in Prairie Potholes has surged: up 169% on the route-weighted index since 1969.

+169%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 →
34Routes 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 →

Blue Grosbeak has surged in Prairie Potholes: up 169% on the route-weighted index since 1969.

Blue Grosbeak In Prairie Potholes Population Forecast

If the recent trend holds, Blue Grosbeak in Prairie Potholes is projected to fall about 55% by 2030 — from 0.81 in 2025 to a central estimate of 0.37 (95% range 0.06–0.68). A 5-year backtest shows a typical error of ±58.9%, with 20% of held-out values landing inside the 95% band.

-55%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 →
0.37Projected 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 →
0.06–0.6895% 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 →
±58.9%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, Blue Grosbeak in Prairie Potholes is projected to fall about 55% by 2030 — from 0.81 in 2025 to a central estimate of 0.37 (95% range 0.06–0.68). A 5-year backtest shows a typical error of ±58.9%, with 20% 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 →
20260.360.040.67
20270.360.050.67
20280.360.050.68
20290.370.050.68
20300.370.060.68

Routes In Prairie Potholes

Routes recording Blue Grosbeak in Prairie Potholes.
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 →
SpartaNEBRASKA82025
TrippSOUTH-DAKOTA82025
MidwayNEBRASKA72025
Eagle CreekNEBRASKA62025
TildenNEBRASKA62025
HowardSOUTH-DAKOTA62025
ChandlerMINNESOTA52025
Winside 2NEBRASKA42022
MadisonNEBRASKA32025
ClareIOWA22019
HuntleyMINNESOTA22024
WorthingtonMINNESOTA22024
Chokio NorthMINNESOTA22011
WinsideNEBRASKA22002
PoncaNEBRASKA22025
LennoxSOUTH-DAKOTA22025
ScrantonIOWA12025
TitonkaIOWA12025
MccallsburgIOWA12025
Redwood FallMINNESOTA12015
GluekMINNESOTA12018
GlyndonMINNESOTA12012
FairmontMINNESOTA12025
TracyMINNESOTA12025
TylerMINNESOTA12024

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