BirdAnalyst
Species · BCR 19 · BBS 2025 Release · 1966–2024

Black-crowned Night Heron In Central Mixed Grass Prairie

All regionsCentral Mixed Grass PrairieWetland birds

Black-crowned Night Heron in Central Mixed Grass Prairie has collapsed: down 97% on the route-weighted index since 1969.

-97%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 →
39Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 collapsed in Central Mixed Grass Prairie: down 97% on the route-weighted index since 1969.

Black-crowned Night Heron In Central Mixed Grass Prairie Population Forecast

If the recent trend holds, Black-crowned Night Heron in Central Mixed Grass Prairie is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±152.7%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029TrendPercent 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 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.795% 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 →
±152.7%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 Central Mixed Grass Prairie is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±152.7%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.000.001.7
20260.000.001.7
20270.000.001.7
20280.000.001.7
20290.000.001.7

Routes In Central Mixed Grass Prairie

Routes recording Black-crowned Night Heron in Central Mixed Grass Prairie.
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 →
AlbertKANSAS32023
Crescent LkNEBRASKA32017
Wheeler CoNEBRASKA32011
KennedyNEBRASKA22010
MullenNEBRASKA22001
ErickOKLAHOMA21990
ChildressTEXAS22008
HackberryTEXAS21993
WellingtonKANSAS12023
DaltonKANSAS12017
St JohnKANSAS11999
CoatsKANSAS11975
ColdwaterKANSAS12004
KanopolisKANSAS11996
PhillipsburgKANSAS12007
GoveKANSAS11977
MisslerKANSAS11994
SolomonKANSAS11996
BerwetKANSAS12006
StrattonNEBRASKA12004
SurpriseNEBRASKA11993
Swan LakeNEBRASKA12021
JohnstownNEBRASKA11977
Piester LakeNEBRASKA12018
ArthurNEBRASKA12017

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