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Species · Oregon · BBS 2026 Release · 1966–2025

Pied-billed Grebe Population Trend in Oregon

All statesWetland birds

Pied-billed Grebe in Oregon has declined: down 26% on the route-weighted index since 1970.

-26%Since 1970TrendPercent 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 →
39Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Pied-billed Grebe Trends in OregonNotable 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 Pied-billed Grebe in Oregon. See the full index history below.

Pied-billed Grebe Population Forecast in Oregon

If the recent trend holds, Pied-billed Grebe in Oregon is projected to fall about 18% by 2030 — from 0.14 in 2025 to a central estimate of 0.11 (95% range 0.00–0.26). A 5-year backtest shows a typical error of ±46.1%, with 100% of held-out values landing inside the 95% band.

-18%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 →
0.11Projected 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 →
0.00–0.2695% 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 →
±46.1%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, Pied-billed Grebe in Oregon is projected to fall about 18% by 2030 — from 0.14 in 2025 to a central estimate of 0.11 (95% range 0.00–0.26). A 5-year backtest shows a typical error of ±46.1%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.120.000.26
20270.120.000.26
20280.120.000.26
20290.120.000.26
20300.110.000.26

Pied-billed Grebe Survey Routes in Oregon

Routes recording Pied-billed Grebe in Oregon.
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 →
Barnes Val519871985
Lone Rock320152015
Warner Vally320241997
Davis Lake320252000
Modoc Point 2220252025
Santiam220182006
Lapham Res.220252025
Umpqua219791979
Adair220251972
Elk Lake220181977
Merrill220131995
Catlow Rim220252012
Mcminnville220172017
Nicolai Mtn.120082007
Winberry119941992
Dell Spring119761968
Wedderburn120232023
Malheur Nwr119891986
Modoc Point120181971
Alvord Lake120192019
Emigrant Lake 2120102010
Bly 2120242007
Joseph119881977
Dayton119781978
Clover Creek120252025

Pied-billed Grebe Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwisconsinwyoming

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