BirdAnalyst
Species · BCR 30 · BBS 2026 Release · 1966–2025

Forster's Tern In New England / Mid-Atlantic Coast

All regionsNew England / Mid-Atlantic CoastWetland birds

Forster's Tern in New England / Mid-Atlantic Coast has surged: up 126% on the route-weighted index since 1968.

+126%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 →
31Routes 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 increasecomputed 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 →

Forster's Tern has surged in New England / Mid-Atlantic Coast: up 126% on the route-weighted index since 1968.

Forster's Tern In New England / Mid-Atlantic Coast Population Forecast

If the recent trend holds, Forster's Tern in New England / Mid-Atlantic Coast is projected to rise about 141% by 2030 — from 0.18 in 2025 to a central estimate of 0.42 (95% range 0.08–0.77). A 5-year backtest shows a typical error of ±83.9%, with 100% of held-out values landing inside the 95% band.

+141%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 →
0.42Projected 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 →
0.08–0.7795% 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 →
±83.9%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, Forster's Tern in New England / Mid-Atlantic Coast is projected to rise about 141% by 2030 — from 0.18 in 2025 to a central estimate of 0.42 (95% range 0.08–0.77). A 5-year backtest shows a typical error of ±83.9%, 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 →
20260.400.060.75
20270.410.060.76
20280.410.070.76
20290.420.070.77
20300.420.080.77

Routes In New England / Mid-Atlantic Coast

Routes recording Forster's Tern 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 →
Del HavenNEW-JERSEY111991
Six PointsNEW-JERSEY72014
Ocean CityNEW-JERSEY72025
Cape May ChNEW-JERSEY72013
White StoneVIRGINIA71996
Golden HillMARYLAND52006
Bethany BchDELAWARE41989
PepperboxDELAWARE42016
VillasNEW-JERSEY41981
HuntingtonNEW-YORK42023
SharpsVIRGINIA41999
HarringtonDELAWARE32025
Pepperbox 2DELAWARE32025
QuinbyVIRGINIA31983
Lowes XrdsDELAWARE21991
PomfretMARYLAND21974
EastonMARYLAND22013
MadisonMARYLAND22021
FruitlandMARYLAND21985
CokesburyMARYLAND22015
NewarkMARYLAND22018
WinslowNEW-JERSEY22000
DoverDELAWARE11966
FrankfordDELAWARE12006
BlackbirdDELAWARE12024

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