BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Clark's Grebe

PodicipedidaeWetland birdsAechmophorus clarkii

Clark's Grebe has edged up: up 21% on the route-weighted index since 1988.

+21%Since 1988TrendPercent 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 →
70RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
38Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Clark's Grebe

The Clark's Grebe (Aechmophorus clarkii) is a North American member of the Grebes (Podicipedidae). In this analysis it is grouped with the wetland birds.

Size
9–21.5 in long (23–55 cm) — a diving water bird (typical for the family)
Habitat
Marshes, ponds, lakeshores and other freshwater wetlands.
Diet
Aquatic invertebrates, small fish, frogs and plant matter.
Range
Recorded on 70 Breeding Bird Survey routes across 12 states, most concentrated in the Great Basin.
Family
Podicipedidae · Wetland birds

Notable Clark's Grebe TrendsNotable 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 Clark's Grebe. See the full index history below.

Clark's Grebe Population Forecast

If the recent trend holds, Clark's Grebe is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±165.6%, 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 →
0.04Projected 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 →
0.00–0.0795% 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 →
±165.6%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, Clark's Grebe is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±165.6%, with 100% of held-out values landing inside the 95% band.19862029
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 →
20250.030.000.07
20260.040.000.07
20270.040.000.07
20280.040.000.07
20290.040.000.07

Where the Clark's Grebe Is Detected

BBS routes recording Clark's Grebe, sized by most recent count.

Clark's Grebe Population Trend by State

Clark's Grebe population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Arizonainsufficient datan/a2
California-34%198823
Coloradoinsufficient datan/a5
Idaho-37%19907
Montanainsufficient datan/a2
Nebraskainsufficient datan/a1
Nevadainsufficient datan/a2
North Dakotainsufficient datan/a4
Oregon+38%19896
South Dakotainsufficient datan/a1
Utah+818%19929
Wyominginsufficient datan/a8

Clark's Grebe Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Clark's Grebe population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Great Basin-4%198824
Northern Rockies-59%199615
Coastal California+107%198813

Clark's Grebe Conservation Status

Our route-weighted index shows it up about 21% since 1988.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.