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

Great Blue Heron Population Trend in Washington

All statesWetland birds

Great Blue Heron in Washington has declined: down 46% on the route-weighted index since 1970.

-46%Since 1970
83Routes In State
56Years

Notable Great Blue Heron Trends in Washington

No notable trend signals for Great Blue Heron in Washington. See the full index history below.

Great Blue Heron Population Forecast in Washington

If the recent trend holds, Great Blue Heron in Washington is projected to rise about 11% by 2029 — from 0.51 in 2024 to a central estimate of 0.56 (95% range 0.02–1.1). A 5-year backtest shows a typical error of ±64.8%, with 100% of held-out values landing inside the 95% band.

+11%Change by 2029
0.56Projected 2029 index
0.02–1.195% range
±64.8%Backtest error
19682029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20250.600.051.1
20260.590.051.1
20270.580.041.1
20280.570.031.1
20290.560.021.1

Great Blue Heron Survey Routes in Washington

Routes recording Great Blue Heron in Washington.
Ilwaco720241975
Othello619911983
Yakima420241993
Issaquah319841970
Reardan320211968
Odessa320232000
Hanford Site319961988
Port Angeles220241970
Moses Lake220211973
Camas220091977
Snowden220221983
Ewan220191983
Spring Lake220222015
Curlew220051999
Malden220241998
Harwood219971995
Bay View220171993
Carnation220241989
Ewan 2220242023
Columbia Nwr220221992
Turnbull Nwr220231993
Horn Rapids220242005
Ozette120241975
Warm Beach120171968
Newhalem119861981

Great Blue Heron Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

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