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Species · Pennsylvania · BBS 2026 Release · 1966–2025

Yellow-billed Cuckoo Population Trend in Pennsylvania

All statesForest birds

Yellow-billed Cuckoo in Pennsylvania has held roughly steady: down 6% on the route-weighted index since 1968.

-6%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 →
134Routes 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 →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Yellow-billed Cuckoo Trends in PennsylvaniaNotable 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 Yellow-billed Cuckoo in Pennsylvania. See the full index history below.

Yellow-billed Cuckoo Population Forecast in Pennsylvania

If the recent trend holds, Yellow-billed Cuckoo in Pennsylvania is projected to rise about 165% by 2030 — from 0.56 in 2025 to a central estimate of 1.5 (95% range 0.13–2.8). A 5-year backtest shows a typical error of ±70.4%, with 100% of held-out values landing inside the 95% band.

+165%Change by 2030TrendPercent 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 →
1.5Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.13–2.895% 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 →
±70.4%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, Yellow-billed Cuckoo in Pennsylvania is projected to rise about 165% by 2030 — from 0.56 in 2025 to a central estimate of 1.5 (95% range 0.13–2.8). A 5-year backtest shows a typical error of ±70.4%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20261.50.142.9
20271.50.142.9
20281.50.142.8
20291.50.142.8
20301.50.132.8

Yellow-billed Cuckoo Survey Routes in Pennsylvania

Routes recording Yellow-billed Cuckoo in Pennsylvania.
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 →
Sproul Sf-B1820232003
Rosecrans1720231969
Mawr Glen1220241983
Big Flat1019811966
Jeannette1020221981
Bendersville1020241990
Roulette720211973
Wakena720191969
Ryde720051968
Aspers719831970
Bald Eagle620231971
Waterstreet620231968
Warrens Mill620251971
Stoneybreak620241992
Ramsey520231969
Little Marsh520231985
Starlight519831971
Ltl Pine Cr520241990
Slippery Rk419911990
Odin420171973
Sardis419731970
West Grove419791967
Duboistown420221988
Tussey Mtn.420251993
Scheafferstn320011966

Yellow-billed Cuckoo Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.