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

Great Blue Heron In Atlantic Northern Forest

All regionsAtlantic Northern ForestWetland birds

Great Blue Heron in Atlantic Northern Forest has risen sharply: up 62% on the route-weighted index since 1968.

+62%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 →
136Routes 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 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 →

Great Blue Heron has risen sharply in Atlantic Northern Forest: up 62% on the route-weighted index since 1968.

Great Blue Heron In Atlantic Northern Forest Population Forecast

If the recent trend holds, Great Blue Heron in Atlantic Northern Forest is projected to rise about 19% by 2030 — from 0.29 in 2025 to a central estimate of 0.35 (95% range 0.12–0.58). A 5-year backtest shows a typical error of ±48.7%, with 100% of held-out values landing inside the 95% band.

+19%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 →
0.35Projected 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 →
0.12–0.5895% 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 →
±48.7%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, Great Blue Heron in Atlantic Northern Forest is projected to rise about 19% by 2030 — from 0.29 in 2025 to a central estimate of 0.35 (95% range 0.12–0.58). A 5-year backtest shows a typical error of ±48.7%, 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 →
20260.350.120.58
20270.350.120.58
20280.350.120.58
20290.350.120.58
20300.350.120.58

Routes In Atlantic Northern Forest

Routes recording Great Blue Heron 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 →
Jefferson HlNEW-HAMPSHIRE71995
SabattisNEW-YORK51983
Brownfield 2MAINE32017
LempsterNEW-HAMPSHIRE32022
St Regis FlsNEW-YORK32016
S ReadingVERMONT32019
W RutlandVERMONT32025
WatervilleVERMONT31979
GreenwoodMAINE22021
HarmonyMAINE22017
DebloisMAINE22007
Seboomook LkMAINE21999
CambridgeMAINE22010
WytopitlockMAINE21982
MedwayMAINE22016
Pillsbury PdMAINE21968
Horse MtnMAINE21990
AshlandMAINE21999
St DavidMAINE21992
RomeMAINE22024
CheshireMASSACHUSETTS21991
HancockMASSACHUSETTS22011
Blue Ridge NNEW-YORK22015
North RiverNEW-YORK22001
Dexter LakeNEW-YORK21975

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