Species · Maryland · BBS 2025 Release · 1966–2024
Black-billed Cuckoo Population Trend in Maryland
Black-billed Cuckoo in Maryland has collapsed: down 77% on the route-weighted index since 1968.
-77%Since 1968
53Routes In State
54Years
Notable Black-billed Cuckoo Trends in Maryland
long arc declinecomputed index
Black-billed Cuckoo has collapsed in Maryland: down 77% on the route-weighted index since 1968.
Black-billed Cuckoo Population Forecast in Maryland
If the recent trend holds, Black-billed Cuckoo in Maryland is projected to fall about 75% by 2026 — from 0.10 in 2021 to a central estimate of 0.03 (95% range 0.00–0.17). A 5-year backtest shows a typical error of ±41.2%, with 100% of held-out values landing inside the 95% band.
-75%Change by 2026
0.03Projected 2026 index
0.00–0.1795% range
±41.2%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2022 | 0.04 | 0.00 | 0.18 |
| 2023 | 0.03 | 0.00 | 0.18 |
| 2024 | 0.03 | 0.00 | 0.18 |
| 2025 | 0.03 | 0.00 | 0.17 |
| 2026 | 0.03 | 0.00 | 0.17 |
Black-billed Cuckoo Survey Routes in Maryland
| Upper Xrds | 4 | 2004 | 1975 |
| Wolfsville | 3 | 1998 | 1977 |
| Emmitsburg | 3 | 1987 | 1975 |
| Berlin | 3 | 1990 | 1981 |
| Newark | 3 | 1981 | 1978 |
| Mt Nebo | 2 | 1990 | 1983 |
| Bachman Mill | 2 | 1984 | 1969 |
| Elkton | 2 | 1983 | 1966 |
| Snow Hill | 2 | 1968 | 1968 |
| Finzel | 2 | 2021 | 2004 |
| Piney Grove | 2 | 2002 | 1995 |
| Floyd | 1 | 2013 | 1966 |
| Vindex | 1 | 2019 | 1966 |
| Oldtown | 1 | 2007 | 1972 |
| Potomac Park | 1 | 2021 | 1986 |
| Williamsport | 1 | 2017 | 1991 |
| Smithsburg | 1 | 1987 | 1966 |
| Silver Spg | 1 | 1989 | 1989 |
| Olney | 1 | 1981 | 1966 |
| Warfieldsbrg | 1 | 1990 | 1966 |
| Fowblesburg | 1 | 2009 | 1967 |
| Eklo | 1 | 1993 | 1966 |
| Randallstown | 1 | 1989 | 1967 |
| Van Bibber | 1 | 2000 | 1966 |
| Walnut | 1 | 2004 | 2004 |
Black-billed Cuckoo Population Trend in Other States
alabamaarkansascoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansaskentuckymainemassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.