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

Black-billed Cuckoo Population Trend in Virginia

All statesGeneralists

Black-billed Cuckoo in Virginia has collapsed: down 90% on the route-weighted index since 1968.

-90%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 →
42Routes 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 →
52YearsYears 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 VirginiaNotable 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 Virginia: down 90% on the route-weighted index since 1968.

Black-billed Cuckoo Population Forecast in Virginia

If the recent trend holds, Black-billed Cuckoo in Virginia is projected to fall about 100% by 2029 — from 0.06 in 2024 to a central estimate of 0.00 (95% range 0.00–0.35). A 5-year backtest shows a typical error of ±196.9%, 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 →
0.00–0.3595% 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 →
±196.9%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 Virginia is projected to fall about 100% by 2029 — from 0.06 in 2024 to a central estimate of 0.00 (95% range 0.00–0.35). A 5-year backtest shows a typical error of ±196.9%, 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 →
20250.000.000.35
20260.000.000.35
20270.000.000.35
20280.000.000.35
20290.000.000.35

Black-billed Cuckoo Survey Routes in Virginia

Routes recording Black-billed Cuckoo in Virginia.
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 →
Stanley319931966
Edinburg319921969
Nat Tunnel319971992
Carters Brdg319811969
Taylorstown219851968
W Augusta219991967
Tryme220111975
Shipman219951969
White Stone219721970
Front Royal220111995
Star Tannery120051980
Churchville120241970
Rural Retrt120161990
Gr North Mtn120241994
Glenwood119981998
David119901990
Isom120111969
Putnam119931971
Covington120182011
New Market120131995
Fincastle119791966
Natural Brid119801974
Mountain Lk.120072007
Big Island119701970
Covesville119781978

Black-billed Cuckoo Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseetexasvermontwest-virginiawisconsinwyoming

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