BirdAnalyst
Species · BCR 17 · BBS 2025 Release · 1966–2024

Western Grebe In Badlands and Prairies

All regionsBadlands and PrairiesWetland birds

Western Grebe in Badlands and Prairies has risen sharply: up 55% on the route-weighted index since 1991.

+55%Since 1991TrendPercent 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 →
18Routes 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 →
28YearsYears 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 →

Western Grebe has risen sharply in Badlands and Prairies: up 55% on the route-weighted index since 1991.

Western Grebe In Badlands and Prairies Population Forecast

If the recent trend holds, Western Grebe in Badlands and Prairies is projected to stay roughly flat through 2029, near 0.09 (95% range 0.00–0.20). A 5-year backtest shows a typical error of ±228.8%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.09Projected 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 →
0.00–0.2095% 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 →
±228.8%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, Western Grebe in Badlands and Prairies is projected to stay roughly flat through 2029, near 0.09 (95% range 0.00–0.20). A 5-year backtest shows a typical error of ±228.8%, with 100% of held-out values landing inside the 95% band.19882029
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 →
20250.090.000.20
20260.090.000.20
20270.090.000.20
20280.090.000.20
20290.090.000.20

Routes In Badlands and Prairies

Routes recording Western Grebe 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 →
DwyerWYOMING92016
CottonwoodSOUTH-DAKOTA62022
S. PioneerSOUTH-DAKOTA42021
DaytonWYOMING32011
ShawmutMONTANA22023
HighwoodMONTANA12008
JordanMONTANA12017
Two DotMONTANA12024
LindsayMONTANA12019
TobaccoNORTH-DAKOTA11996
BowmanNORTH-DAKOTA12019
GorhamNORTH-DAKOTA11997
BentleyNORTH-DAKOTA12011
OwankaSOUTH-DAKOTA12014
HardingSOUTH-DAKOTA12013
Cedar PassSOUTH-DAKOTA12002
LacreekSOUTH-DAKOTA12021
WelchWYOMING12014

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