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Species · Louisiana · BBS 2025 Release · 1966–2024

Yellow-crowned Night Heron Population Trend in Louisiana

All statesWetland birds

Yellow-crowned Night Heron in Louisiana has surged: up 124% on the route-weighted index since 1969.

+124%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 →
78Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Yellow-crowned Night Heron Trends in LouisianaNotable 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 →

Yellow-crowned Night Heron has surged in Louisiana: up 124% on the route-weighted index since 1969.

Yellow-crowned Night Heron Population Forecast in Louisiana

If the recent trend holds, Yellow-crowned Night Heron in Louisiana is projected to stay roughly flat through 2029, near 3.5 (95% range 0.00–8.2). A 5-year backtest shows a typical error of ±138.7%, with 100% of held-out values landing inside the 95% band.

-6%Change 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 →
3.5Projected 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 →
0.00–8.295% 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 →
±138.7%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, Yellow-crowned Night Heron in Louisiana is projected to stay roughly flat through 2029, near 3.5 (95% range 0.00–8.2). A 5-year backtest shows a typical error of ±138.7%, 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 →
20253.50.008.2
20263.50.008.2
20273.50.008.2
20283.50.008.2
20293.50.008.2

Yellow-crowned Night Heron Survey Routes in Louisiana

Routes recording Yellow-crowned Night Heron in Louisiana.
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 →
Ramah9020241988
Morgan City2319861968
Atchafalaya1420241989
Creole1219801967
Keystone1220131971
Kraemer920241997
Forked Island920242016
Esther820241989
Junior719911987
Maurice720241989
Mer Rouge419851967
Ville Platte420171988
Carlisle319881987
Lafitte319911967
Shaw320241972
Larose319901990
Womack320242024
Derry 2320221995
Sabine Nwr 2320142012
Woodlawn320212008
Freetown220191978
Bickham219931985
Fishville220112011
Cypress219811967
Clay220011970

Yellow-crowned Night Heron Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianakansaskentuckymarylandmississippimissourinew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniasouth-carolinatennesseetexasvirginiawest-virginia

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