BirdAnalyst
Species · North Dakota · BBS 2025 Release · 1966–2024

Black-billed Cuckoo Population Trend in North Dakota

All statesGeneralists

Black-billed Cuckoo in North Dakota has fallen sharply: down 68% on the route-weighted index since 1969.

-68%Since 1969TrendPercent 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 →
48Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-billed Cuckoo Trends in North DakotaNotable 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 declinecomputed 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 →

Black-billed Cuckoo has fallen sharply in North Dakota: down 68% on the route-weighted index since 1969.

Black-billed Cuckoo Population Forecast in North Dakota

If the recent trend holds, Black-billed Cuckoo in North Dakota is projected to fall about 100% by 2029 — from 0.33 in 2024 to a central estimate of 0.00 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±160.1%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–1.195% 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 →
±160.1%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, Black-billed Cuckoo in North Dakota is projected to fall about 100% by 2029 — from 0.33 in 2024 to a central estimate of 0.00 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±160.1%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.000.001.1
20260.000.001.1
20270.000.001.1
20280.000.001.1
20290.000.001.1

Black-billed Cuckoo Survey Routes in North Dakota

Routes recording Black-billed Cuckoo in North Dakota.
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 →
Kempton820121969
Tobacco820061968
Lark519821971
Nash420101983
Walcott220211967
Emerado220241973
Cooperstown220231970
Rolla220021971
Niles220001989
Stanley220071967
Zap219981967
Roosevelt Pk220161987
Golva220071979
Douglas Crk220101982
Sheyenne Lk220101980
Turtle Mtns220191980
Carson219971988
Solen220242008
Forman120181973
Sydney119811967
Edgeley120241980
Lake George120061971
Danzig119931991
Wimbledon120151981
Horsehead Lk120061980

Black-billed Cuckoo Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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