BirdAnalyst
Species · Indiana · BBS 2025 Release · 1966–2024

Black-billed Cuckoo Population Trend in Indiana

All statesGeneralists

Black-billed Cuckoo in Indiana has collapsed: down 85% on the route-weighted index since 1968.

-85%Since 1968TrendPercent 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 →
45Routes 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 →
54YearsYears 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 IndianaNotable 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 collapsed in Indiana: down 85% on the route-weighted index since 1968.

Black-billed Cuckoo Population Forecast in Indiana

If the recent trend holds, Black-billed Cuckoo in Indiana is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.44). A 5-year backtest shows a typical error of ±637.7%, 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 →
0.00Projected 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 →
0.00–0.4495% 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 →
±637.7%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 Indiana is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.44). A 5-year backtest shows a typical error of ±637.7%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20250.000.000.44
20260.000.000.44
20270.000.000.44
20280.000.000.44
20290.000.000.44

Black-billed Cuckoo Survey Routes in Indiana

Routes recording Black-billed Cuckoo in Indiana.
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 →
Kewanna220071981
Galveston220072002
Swayzee219811981
Spencer220091967
Milroy219801970
Brookville219951979
Cumback219831976
Millersburg219811981
Wallace220022002
Packertown 2220082008
Hebron119891967
South Bend119731966
Hoosier119931993
Middlebury120232003
Columbia Cty119891987
Packertown119901971
Ellis120181971
Fowler119881971
W Lafayette120071984
Monticello120081981
Thorntown119891982
Kankakee Sands120242004
Middletown119861986
Muncie119881988
Wabash120111997

Black-billed Cuckoo Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawaregeorgiaidahoillinoisiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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