BirdAnalyst
Species · Mississippi · BBS 2026 Release · 1966–2025

Great Blue Heron Population Trend in Mississippi

All statesWetland birds

Great Blue Heron in Mississippi has surged: up 16× on the route-weighted index since 1969.

16×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 →
68Routes 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 Great Blue Heron Trends in MississippiNotable 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 →

Great Blue Heron has surged in Mississippi: up 16× on the route-weighted index since 1969.

Great Blue Heron Population Forecast in Mississippi

If the recent trend holds, Great Blue Heron in Mississippi is projected to rise about 31% by 2030 — from 2.6 in 2025 to a central estimate of 3.4 (95% range 1.3–5.6). A 5-year backtest shows a typical error of ±61.9%, with 100% of held-out values landing inside the 95% band.

+31%Change by 2030TrendPercent 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 →
3.4Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
1.3–5.695% 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 →
±61.9%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, Great Blue Heron in Mississippi is projected to rise about 31% by 2030 — from 2.6 in 2025 to a central estimate of 3.4 (95% range 1.3–5.6). A 5-year backtest shows a typical error of ±61.9%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20263.21.15.4
20273.31.25.4
20283.31.25.5
20293.41.35.5
20303.41.35.6

Great Blue Heron Survey Routes in Mississippi

Routes recording Great Blue Heron in Mississippi.
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 →
Macon3020251979
Tchula 21719941977
Lake Mary719901974
Dundee620221985
Eagle Lake620252012
Isola520221987
Delta N.F.520181995
Mt Carmel420161990
Panther Swamp Nwr420182016
Commerce319921986
Leaf River320132013
Lake Como320212008
Okatibbee L.320081995
Latimer 2320232021
Tchula 3320231995
Necaise320221982
Beverly220081973
Benton220251977
Utica220081976
Walthall219711971
Duck Hill220251989
Lake220221979
Trace Chickasaw220252012
Monticello220172007
Winterville220112009

Great Blue Heron Population Trend in Other States

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

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.