BirdAnalyst
Species · BCR 12 · BBS 2025 Release · 1966–2024

Green Heron In Boreal Hardwood Transition

All regionsBoreal Hardwood TransitionWetland birds

Green Heron in Boreal Hardwood Transition has held roughly steady: down 4% on the route-weighted index since 1968.

-4%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 →
58YearsYears 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 rise about 23% by 2029 — from 0.13 in 2024 to a central estimate of 0.16 (95% range 0.00–0.36). A 5-year backtest shows a typical error of ±89.1%, with 100% of held-out values landing inside the 95% band.

+23%Change by 2029TrendPercent 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 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.3695% 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 →
±89.1%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 rise about 23% by 2029 — from 0.13 in 2024 to a central estimate of 0.16 (95% range 0.00–0.36). A 5-year backtest shows a typical error of ±89.1%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20250.170.000.36
20260.170.000.36
20270.170.000.36
20280.160.000.36
20290.160.000.36

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
Rib LakeWISCONSIN32023
Lake CityMICHIGAN22010
CathroMICHIGAN22015
Wigwam BayMINNESOTA22023
DebsMINNESOTA22024
McgregorMINNESOTA22000
BrainerdMINNESOTA22011
Cass LakeMINNESOTA21983
ExelandWISCONSIN22023
GilmanWISCONSIN22022
PhillipsWISCONSIN22022
Popple RiverWISCONSIN21974
CrandonWISCONSIN22009
OntonagonMICHIGAN12017
MareniscoMICHIGAN12016
Ned LakeMICHIGAN12021
Crystal FlsMICHIGAN12024
Gibbs CityMICHIGAN12023
Maple GroveMICHIGAN12016
Brocky LakeMICHIGAN12017
WilsonMICHIGAN11984
CunardMICHIGAN12019
Bear LakeMICHIGAN12024
MuskallongeMICHIGAN11994

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