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

American Bittern In Atlantic Northern Forest

All regionsAtlantic Northern ForestWetland birds

American Bittern in Atlantic Northern Forest has fallen sharply: down 56% on the route-weighted index since 1968.

-56%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 →
117Routes 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 →
59YearsYears 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 fallen sharply in Atlantic Northern Forest: down 56% on the route-weighted index since 1968.

American Bittern In Atlantic Northern Forest Population Forecast

If the recent trend holds, American Bittern in Atlantic Northern Forest is projected to rise about 170% by 2030 — from 0.08 in 2025 to a central estimate of 0.22 (95% range 0.04–0.40). A 5-year backtest shows a typical error of ±64.8%, with 100% of held-out values landing inside the 95% band.

+170%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 →
0.22Projected 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 →
0.04–0.4095% 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 →
±64.8%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 Atlantic Northern Forest is projected to rise about 170% by 2030 — from 0.08 in 2025 to a central estimate of 0.22 (95% range 0.04–0.40). A 5-year backtest shows a typical error of ±64.8%, 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 →
20260.230.050.41
20270.230.050.40
20280.230.050.40
20290.220.050.40
20300.220.040.40

Routes In Atlantic Northern Forest

Routes recording American Bittern 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 →
WashburnMAINE52005
St DavidMAINE42005
Northfield 2MAINE41992
NorthfieldMAINE31980
HudsonMAINE32009
Pillsbury PdMAINE31968
Dixvil NotchNEW-HAMPSHIRE32017
W RutlandVERMONT32024
NewcastleMAINE22007
HartfordMAINE22012
ManchesterMAINE21982
FreedomMAINE22022
EastbrookMAINE21985
AuroraMAINE22018
Moose RiverMAINE21989
Forest StaMAINE22000
BoundaryMAINE22011
JeffersonMAINE21996
TopsfieldMAINE21992
Lake MoxieMAINE22009
FranconiaNEW-HAMPSHIRE22003
KasoagNEW-YORK21993
HighmarketNEW-YORK22019
NewcombNEW-YORK21988
InletNEW-YORK22016

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