BirdAnalyst
Species · BCR 12 · BBS 2026 Release · 1966–2025

Green Heron In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionWetland birds

Green Heron in Boreal Hardwood Transition has edged up: up 11% on the route-weighted index since 1968.

+11%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 →
78Routes 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 →

No notable trend signals for Green Heron in Boreal Hardwood Transition. See the full index history below.

Green Heron In Boreal Hardwood Transition Population Forecast

If the recent trend holds, Green Heron in Boreal Hardwood Transition is projected to stay roughly flat through 2030, near 0.16 (95% range 0.00–0.35). A 5-year backtest shows a typical error of ±45.4%, with 100% of held-out values landing inside the 95% band.

+5%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 →
0.16Projected 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 →
0.00–0.3595% 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 →
±45.4%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, Green Heron in Boreal Hardwood Transition is projected to stay roughly flat through 2030, near 0.16 (95% range 0.00–0.35). A 5-year backtest shows a typical error of ±45.4%, 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 →
20260.170.000.36
20270.170.000.36
20280.160.000.35
20290.160.000.35
20300.160.000.35

Routes In Boreal Hardwood Transition

Routes recording Green Heron in Boreal Hardwood Transition.
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 →
MayfieldMICHIGAN32021
Crystal FlsMICHIGAN22025
Lake CityMICHIGAN22010
CathroMICHIGAN22015
Wigwam BayMINNESOTA22023
DebsMINNESOTA22024
BrainerdMINNESOTA22011
Cass LakeMINNESOTA21983
ExelandWISCONSIN22023
PhillipsWISCONSIN22022
Rib LakeWISCONSIN22025
Popple RiverWISCONSIN21974
CrandonWISCONSIN22009
OntonagonMICHIGAN12017
MareniscoMICHIGAN12016
Ned LakeMICHIGAN12021
Gibbs CityMICHIGAN12023
Maple GroveMICHIGAN12016
Brocky LakeMICHIGAN12025
WilsonMICHIGAN11984
CunardMICHIGAN12019
Bear LakeMICHIGAN12024
MuskallongeMICHIGAN11994
GilchristMICHIGAN12004
Pleasant ValMICHIGAN11986

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