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Species · Oklahoma · BBS 2025 Release · 1966–2024

Black-crowned Night Heron Population Trend in Oklahoma

All statesWetland birds

Black-crowned Night Heron in Oklahoma has fallen sharply: down 67% on the route-weighted index since 1969.

-67%Since 1969TrendPercent 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 →
17Routes 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 →
27YearsYears 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 OklahomaNotable 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 →

Black-crowned Night Heron has fallen sharply in Oklahoma: down 67% on the route-weighted index since 1969.

Black-crowned Night Heron Population Forecast in Oklahoma

If the recent trend holds, Black-crowned Night Heron in Oklahoma is projected to fall about 70% by 2026 — from 0.05 in 2021 to a central estimate of 0.02 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±73.5%, with 100% of held-out values landing inside the 95% band.

-70%Change 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 →
0.02Projected 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 →
±73.5%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 Oklahoma is projected to fall about 70% by 2026 — from 0.05 in 2021 to a central estimate of 0.02 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±73.5%, with 100% of held-out values landing inside the 95% band.19672026
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 →
20220.020.000.14
20230.020.000.13
20240.020.000.13
20250.020.000.13
20260.020.000.13

Black-crowned Night Heron Survey Routes in Oklahoma

Routes recording Black-crowned Night Heron in Oklahoma.
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 →
Holdenville219851968
Beggs219681968
Erick219901988
Tatums220211993
Rosston119881988
Blanco119741974
Beaver119881982
Jet120162001
Hooker120001992
Reed120162001
Baron119811981
Duncan119941991
Indianola119961996
Choctaw120051981
Verden119701967
Sickles119921992
Tegarden119821974

Black-crowned Night Heron Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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