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

Great Egret Population Trend in Maryland

All statesWetland birds

Great Egret in Maryland has surged: up 117% on the route-weighted index since 1968.

+117%Since 1968TrendPercent 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 →
25Routes 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 →
58YearsYears 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 Egret Trends in MarylandNotable 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 Egret has surged in Maryland: up 117% on the route-weighted index since 1968.

Great Egret Population Forecast in Maryland

If the recent trend holds, Great Egret in Maryland is projected to rise about 43% by 2029 — from 0.59 in 2024 to a central estimate of 0.85 (95% range 0.33–1.4). A 5-year backtest shows a typical error of ±62.9%, with 80% of held-out values landing inside the 95% band.

+43%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 →
0.85Projected 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 →
0.33–1.495% 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 →
±62.9%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 Egret in Maryland is projected to rise about 43% by 2029 — from 0.59 in 2024 to a central estimate of 0.85 (95% range 0.33–1.4). A 5-year backtest shows a typical error of ±62.9%, with 80% of held-out values landing inside the 95% band.19662029
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 →
20250.810.291.3
20260.820.301.3
20270.830.311.3
20280.840.321.4
20290.850.331.4

Great Egret Survey Routes in Maryland

Routes recording Great Egret in Maryland.
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 →
Honga1520241966
Madison720241966
Easton519871987
Golden Hill420211974
Pomonkey219991967
Melitota220221971
Mardela219951995
Newark220241967
Fair Hill119961996
Olney120232023
Fowblesburg119971997
Walnut120142014
Randallstown119711971
Berlin120191984
Indiantown120111994
Madonna120142014
Tall Timbers119891967
Northeast120132013
Elkton120241982
Piney Neck120151996
Fruitland119971966
Cokesbury120211989
Sinepuxent119771966
Snow Hill119701970
Nottingham120232023

Great Egret Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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