BirdAnalyst
Species · BCR 30 · BBS 2025 Release · 1966–2024

Ring-billed Gull In New England / Mid-Atlantic Coast

All regionsNew England / Mid-Atlantic CoastWetland birds

Ring-billed Gull in New England / Mid-Atlantic Coast has collapsed: down 81% on the route-weighted index since 1968.

-81%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 →
76Routes 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 →
58YearsYears 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 →

Ring-billed Gull has collapsed in New England / Mid-Atlantic Coast: down 81% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Ring-billed Gull in New England / Mid-Atlantic Coast is projected to rise about 187% by 2029 — from 0.28 in 2024 to a central estimate of 0.79 (95% range 0.00–2.5). A 5-year backtest shows a typical error of ±1892.9%, with 100% of held-out values landing inside the 95% band.

+187%Change 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 →
0.79Projected 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 →
0.00–2.595% 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 →
±1892.9%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, Ring-billed Gull in New England / Mid-Atlantic Coast is projected to rise about 187% by 2029 — from 0.28 in 2024 to a central estimate of 0.79 (95% range 0.00–2.5). A 5-year backtest shows a typical error of ±1892.9%, 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 →
20250.790.002.5
20260.790.002.5
20270.790.002.5
20280.790.002.5
20290.790.002.5

Routes In New England / Mid-Atlantic Coast

Routes recording Ring-billed Gull in New England / Mid-Atlantic Coast.
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 →
Piney NeckMARYLAND1692017
NewarkMARYLAND1001984
Jones BeachNEW-YORK422013
EastonMARYLAND322005
BlackbirdDELAWARE252017
WesthamptonNEW-YORK242006
Bethany BchDELAWARE201967
Six PointsNEW-JERSEY202024
IndiantownMARYLAND131999
AlbionNEW-JERSEY122022
NortheastMARYLAND82002
WestbrookCONNECTICUT72006
WalnutMARYLAND62005
No WoodburyCONNECTICUT51997
HarringtonDELAWARE52014
FredericaDELAWARE52013
MardelaMARYLAND52007
Lowes XrdsDELAWARE41991
BerlinMARYLAND42016
PurdyNEW-YORK41987
Cape CharlesVIRGINIA42012
WillimanticCONNECTICUT32016
DoverDELAWARE31987
MillsboroDELAWARE32019
MelitotaMARYLAND32017

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