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Species · BCR 14 · BBS 2025 Release · 1966–2024

Herring Gull In Atlantic Northern Forest

All regionsAtlantic Northern ForestWetland birds

Herring Gull in Atlantic Northern Forest has collapsed: down 95% on the route-weighted index since 1968.

-95%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 →
66Routes 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 →
56YearsYears 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 95% 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 stay roughly flat through 2029, near 0.00 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±733.7%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029TrendPercent 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 2029 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 →
±733.7%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 stay roughly flat through 2029, near 0.00 (95% range 0.00–1.7). A 5-year backtest shows a typical error of ±733.7%, 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 →
20250.000.001.7
20260.000.001.7
20270.000.001.7
20280.000.001.7
20290.000.001.7

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
Seboomook LkMAINE32014
Jefferson HlNEW-HAMPSHIRE31990
Old ForgeNEW-YORK32006
NewcastleMAINE22024
BethelMAINE21989
TurnerMAINE22010
HartfordMAINE21982
BrooksMAINE22016
HancockMAINE22011
CooperMAINE22005
SpeculatorNEW-YORK21984
InletNEW-YORK22017
Post MillsVERMONT21998
New HartfordCONNECTICUT11982
WestbrookMAINE12010
Wilson MillsMAINE12024
GreenwoodMAINE11999
South ArmMAINE11979
Otisfield GrMAINE12012

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