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Species · Maryland · BBS 2025 Release · 1966–2024

Snowy Egret Population Trend in Maryland

All statesWetland birds

Snowy Egret in Maryland has surged: up 93% on the route-weighted index since 1968.

+93%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 →
12Routes 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 Snowy 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 →

Snowy Egret has surged in Maryland: up 93% on the route-weighted index since 1968.

Snowy Egret Population Forecast in Maryland

If the recent trend holds, Snowy Egret in Maryland is projected to fall about 49% by 2029 — from 0.36 in 2024 to a central estimate of 0.18 (95% range 0.00–0.45). A 5-year backtest shows a typical error of ±63.4%, with 100% of held-out values landing inside the 95% band.

-49%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 →
0.18Projected 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 →
0.00–0.4595% 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 →
±63.4%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, Snowy Egret in Maryland is projected to fall about 49% by 2029 — from 0.36 in 2024 to a central estimate of 0.18 (95% range 0.00–0.45). A 5-year backtest shows a typical error of ±63.4%, with 100% 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 →
20250.180.000.45
20260.180.000.45
20270.180.000.45
20280.180.000.45
20290.180.000.45

Snowy Egret Survey Routes in Maryland

Routes recording Snowy 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 →
Honga1020241969
Golden Hill320041974
Easton219761976
Cokesbury220241966
Newark220241967
Pt Republic219851985
Elkton119911970
Madison120241967
Sinepuxent119761966
Snow Hill119741967
Berlin120212019
Tall Timbers119751975

Snowy Egret Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianakansaslouisianamainemassachusettsmississippimissourinebraskanevadanew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaoklahomaoregonrhode-islandsouth-carolinasouth-dakotatennesseetexasutahvirginiawisconsinwyoming

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