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Species · Pennsylvania · BBS 2025 Release · 1966–2024

American Black Duck Population Trend in Pennsylvania

All statesWaterfowl

American Black Duck in Pennsylvania has fallen sharply: down 75% on the route-weighted index since 1968.

-75%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 →
22Routes 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 →
25YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable American Black Duck 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 →

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 →

American Black Duck has fallen sharply in Pennsylvania: down 75% on the route-weighted index since 1968.

American Black Duck Population Forecast in Pennsylvania

If the recent trend holds, American Black Duck in Pennsylvania is projected to stay roughly flat through 2026, near 0.00 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±67.4%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2026TrendPercent 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 2026 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1395% 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 →
±67.4%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, American Black Duck in Pennsylvania is projected to stay roughly flat through 2026, near 0.00 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±67.4%, with 100% of held-out values landing inside the 95% band.19662026
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 →
20220.010.000.13
20230.000.000.13
20240.000.000.13
20250.000.000.13
20260.000.000.13

American Black Duck Survey Routes in Pennsylvania

Routes recording American Black Duck 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 →
Jefferson1619761966
Gatchelville1019721972
Clover319951991
Brunnerville320001974
Ferris Crnrs220162016
Wild Creek219921992
Susquehanna220142014
Duvall220212021
Pottstown219791979
West Grove219721972
Teepleville119701966
Ridgway119671967
Little Marsh120042004
Mawr Glen119681968
Rush119871987
Honesdale120041983
Starlight119701970
Greentown120051986
Portersville119751975
Mount Joy119901990
Clearfield119881988
Drehersville119711971

American Black Duck Population Trend in Other States

alabamaconnecticutdelawareindianamainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiorhode-islandvermontvirginiawest-virginiawisconsin

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