BirdAnalyst
Species · BCR 29 · BBS 2026 Release · 1966–2025

Green Heron In Piedmont

All regionsPiedmontWetland birds

Green Heron in Piedmont has fallen sharply: down 52% on the route-weighted index since 1968.

-52%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 →
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 →

Green Heron has fallen sharply in Piedmont: down 52% on the route-weighted index since 1968.

Green Heron In Piedmont Population Forecast

If the recent trend holds, Green Heron in Piedmont is projected to rise about 37% by 2030 — from 0.16 in 2025 to a central estimate of 0.22 (95% range 0.00–0.55). A 5-year backtest shows a typical error of ±34.4%, with 100% of held-out values landing inside the 95% band.

+37%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 →
0.00–0.5595% 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 →
±34.4%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 rise about 37% by 2030 — from 0.16 in 2025 to a central estimate of 0.22 (95% range 0.00–0.55). A 5-year backtest shows a typical error of ±34.4%, 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 →
20260.260.000.58
20270.250.000.58
20280.240.000.57
20290.230.000.56
20300.220.000.55

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
Mount AiryNORTH-CAROLINA42022
PartlowVIRGINIA42006
LincolntonGEORGIA32015
HollonvilleGEORGIA32003
EarltonMARYLAND32019
MooresvilleNORTH-CAROLINA31996
CallNORTH-CAROLINA32016
ShrewsburyPENNSYLVANIA32012
HallVIRGINIA32014
AthensGEORGIA22024
StockbridgeGEORGIA22014
Sunny SideGEORGIA22018
Rock BranchGEORGIA22024
EmmitsburgMARYLAND22025
Pleasant ValMARYLAND22018
MadisonNORTH-CAROLINA21985
Mooresville 2NORTH-CAROLINA22014
SheffieldNORTH-CAROLINA22013
MonticelloNORTH-CAROLINA22023
OsmondNORTH-CAROLINA22025
Mt GretnaPENNSYLVANIA21988
LabottPENNSYLVANIA21983
Mt Gretna 2PENNSYLVANIA22019

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