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

Little Blue Heron Population Trend in Virginia

All statesWetland birds

Little Blue Heron in Virginia has fallen sharply: down 66% on the route-weighted index since 1968.

-66%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 →
7Routes 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 →
18YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Little Blue Heron Trends in VirginiaNotable 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 declinecomputed 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 →

Little Blue Heron has fallen sharply in Virginia: down 66% on the route-weighted index since 1968.

Little Blue Heron Population Forecast in Virginia

If the recent trend holds, Little Blue Heron in Virginia is projected to stay roughly flat through 2023, near 0.02 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±18.9%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2023TrendPercent 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 →
0.02Projected 2023 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0495% 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 →
±18.9%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, Little Blue Heron in Virginia is projected to stay roughly flat through 2023, near 0.02 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±18.9%, with 100% of held-out values landing inside the 95% band.19662023
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 →
20190.020.000.04
20200.020.000.04
20210.020.000.04
20220.020.000.04
20230.020.000.04

Little Blue Heron Survey Routes in Virginia

Routes recording Little Blue Heron in Virginia.
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 →
Quinby219951974
Branchville219861981
Newsoms119921992
Backbay119691966
Truhart119971997
Chincoteag W120181995
Cape Charles120172000

Little Blue Heron Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoiskansaskentuckylouisianamarylandmassachusettsmississippimissourinew-jerseynew-yorknorth-carolinanorth-dakotaoklahomapennsylvaniarhode-islandsouth-carolinatennesseetexas

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