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Species · Arkansas · BBS 2025 Release · 1966–2024

Pied-billed Grebe Population Trend in Arkansas

All statesWetland birds

Pied-billed Grebe in Arkansas has surged: up 185% on the route-weighted index since 1975.

+185%Since 1975TrendPercent 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 →
5Routes 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 →
22YearsYears 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 ArkansasNotable 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 →

Pied-billed Grebe has surged in Arkansas: up 185% on the route-weighted index since 1975.

Pied-billed Grebe Population Forecast in Arkansas

If the recent trend holds, Pied-billed Grebe in Arkansas is projected to fall about 50% by 2028 — from 0.17 in 2023 to a central estimate of 0.08 (95% range 0.00–0.18). A 5-year backtest shows a typical error of ±48.6%, with 60% of held-out values landing inside the 95% band.

-50%Change by 2028TrendPercent 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 →
0.08Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1895% 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 →
±48.6%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 Arkansas is projected to fall about 50% by 2028 — from 0.17 in 2023 to a central estimate of 0.08 (95% range 0.00–0.18). A 5-year backtest shows a typical error of ±48.6%, with 60% of held-out values landing inside the 95% band.19692028
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 →
20240.080.000.17
20250.080.000.17
20260.080.000.18
20270.080.000.18
20280.080.000.18

Pied-billed Grebe Survey Routes in Arkansas

Routes recording Pied-billed Grebe in Arkansas.
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 →
South Bend520231969
Hughes119971978
Harrisburg120002000
Rupert119711971
Maynard120032003

Pied-billed Grebe Population Trend in Other States

alabamaalaskaarizonacaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwisconsinwyoming

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