BirdAnalyst
Species · BCR 29 · BBS 2025 Release · 1966–2024

Green Heron In Piedmont

All regionsPiedmontWetland birds

Green Heron in Piedmont has declined: down 50% on the route-weighted index since 1968.

-50%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 →
150Routes 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 Piedmont. See the full index history below.

Green Heron In Piedmont Population Forecast

If the recent trend holds, Green Heron in Piedmont is projected to stay roughly flat through 2029, near 0.24 (95% range 0.00–0.57). A 5-year backtest shows a typical error of ±21.4%, with 100% of held-out values landing inside the 95% band.

-2%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 →
0.24Projected 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 →
0.00–0.5795% 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 →
±21.4%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 Piedmont is projected to stay roughly flat through 2029, near 0.24 (95% range 0.00–0.57). A 5-year backtest shows a typical error of ±21.4%, 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 →
20250.270.000.60
20260.270.000.59
20270.260.000.59
20280.250.000.58
20290.240.000.57

Routes In Piedmont

Routes recording Green Heron in Piedmont.
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 →
YoungsvilleNORTH-CAROLINA52023
HebronGEORGIA42011
OlneyMARYLAND42024
Mount AiryNORTH-CAROLINA42022
PartlowVIRGINIA42006
LincolntonGEORGIA32015
HollonvilleGEORGIA32003
WhitesburgGEORGIA32023
EmmitsburgMARYLAND32024
WheatonMARYLAND32005
EarltonMARYLAND32019
MooresvilleNORTH-CAROLINA31996
CallNORTH-CAROLINA32016
ShrewsburyPENNSYLVANIA32012
HallVIRGINIA32014
AthensGEORGIA22024
StockbridgeGEORGIA22014
Sunny SideGEORGIA22018
Rock BranchGEORGIA22024
Pleasant ValMARYLAND22018
Croton 2NEW-JERSEY22016
MadisonNORTH-CAROLINA21985
Mooresville 2NORTH-CAROLINA22014
SheffieldNORTH-CAROLINA22013
MonticelloNORTH-CAROLINA22023

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