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Species · BCR 14 · BBS 2026 Release · 1966–2025

Herring Gull In Atlantic Northern Forest

All regionsAtlantic Northern ForestWetland birds

Herring Gull in Atlantic Northern Forest has collapsed: down 90% on the route-weighted index since 1968.

-90%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 →
67Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 collapsed in Atlantic Northern Forest: down 90% on the route-weighted index since 1968.

Herring Gull In Atlantic Northern Forest Population Forecast

If the recent trend holds, Herring Gull in Atlantic Northern Forest is projected to fall about 100% by 2030 — from 0.10 in 2025 to a central estimate of 0.00 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±639.7%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2030TrendPercent 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 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.795% 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 →
±639.7%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 Atlantic Northern Forest is projected to fall about 100% by 2030 — from 0.10 in 2025 to a central estimate of 0.00 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±639.7%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.000.001.7
20270.000.001.7
20280.000.001.7
20290.000.001.7
20300.000.001.7

Routes In Atlantic Northern Forest

Routes recording Herring Gull in Atlantic Northern Forest.
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 →
Moose RiverMAINE282008
BiddefordMAINE82006
JeffersonMAINE82010
DebloisMAINE52007
GreenvilleMAINE41999
Old Forge 2NEW-YORK42017
HancockMAINE32025
Seboomook LkMAINE32014
Jefferson HlNEW-HAMPSHIRE31990
Old ForgeNEW-YORK32006
NewcastleMAINE22024
BethelMAINE21989
TurnerMAINE22010
HartfordMAINE21982
BrooksMAINE22016
CooperMAINE22005
CornvilleMAINE22025
SpeculatorNEW-YORK21984
InletNEW-YORK22017
New HartfordCONNECTICUT11982
WestbrookMAINE12010
Wilson MillsMAINE12024
GreenwoodMAINE11999
South ArmMAINE11979
Otisfield GrMAINE12012

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.