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

Black-crowned Night Heron Population Trend in Indiana

All statesWetland birds

Black-crowned Night Heron in Indiana has declined: down 40% on the route-weighted index since 1983.

-40%Since 1983TrendPercent 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 →
10Routes 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 Black-crowned Night Heron Trends in IndianaNotable 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 Black-crowned Night Heron in Indiana. See the full index history below.

Black-crowned Night Heron Population Forecast in Indiana

If the recent trend holds, Black-crowned Night Heron in Indiana is projected to stay roughly flat through 2028, near 0.12 (95% range 0.00–0.35). A 5-year backtest shows a typical error of ±335.9%, with 80% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 →
0.12Projected 2028 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 →
±335.9%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-crowned Night Heron in Indiana is projected to stay roughly flat through 2028, near 0.12 (95% range 0.00–0.35). A 5-year backtest shows a typical error of ±335.9%, with 80% of held-out values landing inside the 95% band.19722028
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 →
20240.120.000.35
20250.120.000.35
20260.120.000.35
20270.120.000.35
20280.120.000.35

Black-crowned Night Heron Survey Routes in Indiana

Routes recording Black-crowned Night Heron in Indiana.
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 →
Gary619991982
Indiana Dune520091997
Georgia420012001
Portage220012001
Columbia Cty220232023
Crown Point220002000
Corydon119871987
Ellis119861986
Evansville119721972
Belmont119981998

Black-crowned Night Heron Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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