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

Green Heron Population Trend in Kansas

All statesWetland birds

Green Heron in Kansas has collapsed: down 77% on the route-weighted index since 1969.

-77%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 →
47Routes 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 Green Heron Trends in KansasNotable 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 →

Green Heron has collapsed in Kansas: down 77% on the route-weighted index since 1969.

Green Heron Population Forecast in Kansas

If the recent trend holds, Green Heron in Kansas is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.28). A 5-year backtest shows a typical error of ±48.8%, 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 →
0.03Projected 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 →
0.00–0.2895% 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 →
±48.8%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, Green Heron in Kansas is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.28). A 5-year backtest shows a typical error of ±48.8%, 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 →
20250.070.000.32
20260.060.000.31
20270.050.000.30
20280.040.000.29
20290.030.000.28

Green Heron Survey Routes in Kansas

Routes recording Green Heron in Kansas.
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 →
Albert619931969
Morehead320122001
Solomon320101988
Galesburg220231967
Dalton220051969
Coldwater219821974
Leoville220121976
Pittsburg220182004
Melrose120161967
Humboldt120221972
Lapland120131974
Jewell 2120152015
Wellington119911968
Coats120091967
Ashland120171985
Olathe120171967
Dover120211970
Barclay120181967
Wreford120161969
Ellinor119921970
Chapman119771968
Buckeye120141975
Kanopolis120111971
Gray120121975
Hays119861973

Green Heron Population Trend in Other States

alabamaarizonaarkansascaliforniaconnecticutdelawarefloridageorgiaillinoisindianaiowakentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawashingtonwest-virginiawisconsin

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