BirdAnalyst
Species · Rhode Island · BBS 2025 Release · 1966–2024

American Black Duck Population Trend in Rhode Island

All statesWaterfowl

American Black Duck in Rhode Island has risen sharply: up 57% on the route-weighted index since 1970.

+57%Since 1970TrendPercent 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 →
3Routes 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 →
21YearsYears 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 Rhode IslandNotable 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 increasecomputed 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 risen sharply in Rhode Island: up 57% on the route-weighted index since 1970.

American Black Duck Population Forecast in Rhode Island

If the recent trend holds, American Black Duck in Rhode Island is projected to stay roughly flat through 2009, near 3.6 (95% range 0.75–6.5). A 5-year backtest shows a typical error of ±58.9%, with 80% of held-out values landing inside the 95% band.

-10%Change by 2009TrendPercent 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 →
3.6Projected 2009 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.75–6.595% 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 →
±58.9%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, American Black Duck in Rhode Island is projected to stay roughly flat through 2009, near 3.6 (95% range 0.75–6.5). A 5-year backtest shows a typical error of ±58.9%, with 80% of held-out values landing inside the 95% band.19672009
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 →
20053.40.516.3
20063.40.576.3
20073.50.636.4
20083.60.696.4
20093.60.756.5

American Black Duck Survey Routes in Rhode Island

Routes recording American Black Duck in Rhode Island.
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 →
Block Island420041987
Quonset Pt319781969
Sachuest Pt119881967

American Black Duck Population Trend in Other States

alabamaconnecticutdelawareindianamainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiopennsylvaniavermontvirginiawest-virginiawisconsin

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