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Species · Virginia · BBS 2025 Release · 1966–2024

Herring Gull Population Trend in Virginia

All statesWetland birds

Herring Gull in Virginia has declined: down 46% on the route-weighted index since 1968.

-46%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 →
9Routes 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 →
49YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Herring Gull 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 →

No notable trend signals for Herring Gull in Virginia. See the full index history below.

Herring Gull Population Forecast in Virginia

If the recent trend holds, Herring Gull in Virginia is projected to rise about 12× by 2027 — from 0.09 in 2022 to a central estimate of 1.1 (95% range 0.00–3.6). A 5-year backtest shows a typical error of ±836.3%, with 100% of held-out values landing inside the 95% band.

12×Change by 2027TrendPercent 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 →
1.1Projected 2027 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–3.695% 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 →
±836.3%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, Herring Gull in Virginia is projected to rise about 12× by 2027 — from 0.09 in 2022 to a central estimate of 1.1 (95% range 0.00–3.6). A 5-year backtest shows a typical error of ±836.3%, with 100% of held-out values landing inside the 95% band.19662027
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 →
20231.00.003.6
20241.00.003.6
20251.00.003.6
20261.00.003.6
20271.10.003.6

Herring Gull Survey Routes in Virginia

Routes recording Herring Gull 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 →
Backbay5019711966
Colonial Pky2619981997
Cape Charles2420181992
Quinby1120061967
Chincoteag W420221992
Gloucester220171995
Truhart220051997
Pungo119931993
White Stone120131975

Herring Gull Population Trend in Other States

alabamaalaskacaliforniacoloradoconnecticutdelawarefloridaidahoillinoisindianakansaslouisianamainemarylandmassachusettsmichiganminnesotamontananew-hampshirenew-jerseynew-yorknorth-carolinaohiooregonpennsylvaniarhode-islandsouth-carolinatexasvermontwashingtonwest-virginiawisconsin

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