BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Eared Grebe In Northern Rockies

All regionsNorthern RockiesWetland birds

Eared Grebe in Northern Rockies has surged: up 207% on the route-weighted index since 1976.

+207%Since 1976TrendPercent 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 →
33Routes 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 →
43YearsYears 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 →

Eared Grebe has surged in Northern Rockies: up 207% on the route-weighted index since 1976.

Eared Grebe In Northern Rockies Population Forecast

If the recent trend holds, Eared Grebe in Northern Rockies is projected to rise about 384% by 2029 — from 0.14 in 2024 to a central estimate of 0.65 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±411%, with 100% of held-out values landing inside the 95% band.

+384%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 →
0.65Projected 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 →
0.00–1.595% 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 →
±411%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, Eared Grebe in Northern Rockies is projected to rise about 384% by 2029 — from 0.14 in 2024 to a central estimate of 0.65 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±411%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.610.001.4
20260.620.001.5
20270.630.001.5
20280.640.001.5
20290.650.001.5

Routes In Northern Rockies

Routes recording Eared Grebe in Northern Rockies.
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 →
Neponset ResUTAH502018
YellowstoneWYOMING352018
Hebgen LakeMONTANA322022
Saleratus CrUTAH202016
HarmonyWYOMING132022
Carter 2WYOMING132024
Rock RiverWYOMING112022
MammothWYOMING72016
AnchorWYOMING62016
PathfinderWYOMING52024
LamontWYOMING41991
Mtn ViewWYOMING42022
CascadeIDAHO21983
AugustaMONTANA22015
Red RockMONTANA22010
ErvayWYOMING22022
MckinnonWYOMING21982
Horse CreekWYOMING22012
Fiddler LkWYOMING22004
Green RiverWYOMING21981
RawlinsWYOMING22006
WalcottWYOMING21992
Patrick Draw 2WYOMING21982
Rawlins 2WYOMING22016
KalispellMONTANA12012

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