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Species · Florida · BBS 2025 Release · 1966–2024

Herring Gull Population Trend in Florida

All statesWetland birds

Herring Gull in Florida has fallen sharply: down 59% on the route-weighted index since 1968.

-59%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 →
33YearsYears 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 FloridaNotable 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 →

Herring Gull has fallen sharply in Florida: down 59% on the route-weighted index since 1968.

Herring Gull Population Forecast in Florida

If the recent trend holds, Herring Gull in Florida is projected to fall about 100% by 2027 — from 0.07 in 2022 to a central estimate of 0.00 (95% range 0.00–0.18). A 5-year backtest shows a typical error of ±90.4%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–0.1895% 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 →
±90.4%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, Herring Gull in Florida is projected to fall about 100% by 2027 — from 0.07 in 2022 to a central estimate of 0.00 (95% range 0.00–0.18). A 5-year backtest shows a typical error of ±90.4%, 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 →
20230.000.000.19
20240.000.000.18
20250.000.000.18
20260.000.000.18
20270.000.000.18

Herring Gull Survey Routes in Florida

Routes recording Herring Gull in Florida.
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 →
Vero Beach820132008
Pleasant Grove 2420222010
Homestead220152015
Ft Waltn Bch120091966
Port St Joe119901990
Ft Gadsden119881975
St Augustine119691969
Santa Rosa119891988
Scottsmoor120092009

Herring Gull Population Trend in Other States

alabamaalaskacaliforniacoloradoconnecticutdelawareidahoillinoisindianakansaslouisianamainemarylandmassachusettsmichiganminnesotamontananew-hampshirenew-jerseynew-yorknorth-carolinaohiooregonpennsylvaniarhode-islandsouth-carolinatexasvermontvirginiawashingtonwest-virginiawisconsin

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