Species · BBS 2025 Release · 1966–2024

Little Blue Heron

ArdeidaeWetland birdsEgretta caerulea

Little Blue Heron has fallen sharply: down 63% on the route-weighted index since 1968.

About the Little Blue Heron

The Little Blue Heron (Egretta caerulea) is a North American member of the Herons, Egrets & Bitterns (Ardeidae). In this analysis it is grouped with the wetland birds.

Size
12–51 in long (30–130 cm) — a long-legged wader (typical for the family)
Habitat
Marshes, ponds, lakeshores and other freshwater wetlands.
Diet
Aquatic invertebrates, small fish, frogs and plant matter.
Range
Recorded on 772 Breeding Bird Survey routes across 25 states, most concentrated in the Southeastern Coastal Plain.
Family
Ardeidae · Wetland birds

Notable Little Blue Heron TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

Little Blue Heron has fallen sharply in surveyed states: down 63% on the route-weighted index since 1968.

Little Blue Heron Population Forecast

If the recent trend holds, Little Blue Heron is projected to stay roughly flat through 2029, near 0.32 (95% range 0.06–0.58). A 5-year backtest shows a typical error of ±55%, with 100% of held-out values landing inside the 95% band.

If the recent trend holds, Little Blue Heron is projected to stay roughly flat through 2029, near 0.32 (95% range 0.06–0.58). A 5-year backtest shows a typical error of ±55%, 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 →
20250.340.080.60
20260.330.070.60
20270.330.070.59
20280.330.070.59
20290.320.060.58

Where the Little Blue Heron Is Detected

BBS routes recording Little Blue Heron, sized by most recent count.

Little Blue Heron Population Trend by State

Little Blue Heron population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Alabama-70%196875
Arkansas-78%196937
Connecticutinsufficient datan/a1
Delaware+21%19747
Florida-65%1968120
Georgia-56%196869
Illinois-86%197112
Kansas-64%197610
Kentucky-51%19706
Louisiana-28%196996
Maryland-19%197017
Massachusettsinsufficient datan/a1
Mississippi-54%196849
Missouri-99%196911
New Jersey-58%19749
New Yorkinsufficient datan/a1
North Carolina-84%196927
North Dakotainsufficient datan/a1
Oklahoma-97%196956
Pennsylvaniainsufficient datan/a4
Rhode Islandinsufficient datan/a1
South Carolina-87%196828
Tennessee+196%197010
Texas-32%1969117
Virginia-66%19687

Little Blue Heron Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Little Blue Heron population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Central Mixed Grass Prairie-97%196939
Oaks and Prairies-52%196966
Eastern Tallgrass Prairie-89%197118
Central Hardwoods-24%197024
West Gulf Coastal Plain / Ouachitas-92%196988
Mississippi Alluvial Valley+18%196862
Southeastern Coastal Plain-62%1968262
Appalachian Mountains-70%197013
Piedmont-21%197319
New England / Mid-Atlantic Coast-52%196941
Peninsular Florida-71%196880
Tamaulipan Brushlands-29%197312
Gulf Coastal Prairie+5%196944

Little Blue Heron Conservation Status

Our route-weighted index shows it down about 63% since 1968.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.