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

American Bittern In New England / Mid-Atlantic Coast

All regionsNew England / Mid-Atlantic CoastWetland birds

American Bittern in New England / Mid-Atlantic Coast has collapsed: down 84% on the route-weighted index since 1968.

-84%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 →
34Routes 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 →
42YearsYears 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 →

American Bittern has collapsed in New England / Mid-Atlantic Coast: down 84% on the route-weighted index since 1968.

American Bittern In New England / Mid-Atlantic Coast Population Forecast

If the recent trend holds, American Bittern in New England / Mid-Atlantic Coast is projected to stay roughly flat through 2026, near 0.00 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±228.8%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2026TrendPercent 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 2026 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0495% 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 →
±228.8%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, American Bittern in New England / Mid-Atlantic Coast is projected to stay roughly flat through 2026, near 0.00 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±228.8%, with 100% of held-out values landing inside the 95% band.19662026
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 →
20220.000.000.04
20230.000.000.04
20240.000.000.04
20250.000.000.04
20260.000.000.04

Routes In New England / Mid-Atlantic Coast

Routes recording American Bittern 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 →
AlbionNEW-JERSEY21966
WesthamptonNEW-YORK21993
HuntingtonNEW-YORK21981
WoodstockCONNECTICUT12004
WarrenCONNECTICUT12011
Mid HaddamCONNECTICUT11990
WilmingtonDELAWARE11970
HarringtonDELAWARE11967
Lowes XrdsDELAWARE11970
BlackbirdDELAWARE11997
Kittery PtMAINE12021
Tall TimbersMARYLAND11978
HongaMARYLAND12006
MadisonMARYLAND12008
ViennaMARYLAND11973
E DennisMASSACHUSETTS11974
PrattvilleMASSACHUSETTS11972
NewburyportMASSACHUSETTS12008
MaynardMASSACHUSETTS11996
E PepperellMASSACHUSETTS11989
Warren 2MASSACHUSETTS12017
Ware RiverMASSACHUSETTS11994
BrentwoodNEW-HAMPSHIRE11981
DoverNEW-HAMPSHIRE11986
EpsomNEW-HAMPSHIRE11992

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