BirdAnalyst
Species · BCR 11 · BBS 2025 Release · 1966–2024

Green Heron In Prairie Potholes

All regionsPrairie PotholesWetland birds

Green Heron in Prairie Potholes has declined: down 38% on the route-weighted index since 1971.

-38%Since 1971TrendPercent 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 →
36Routes 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 →
47YearsYears 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 Prairie Potholes. See the full index history below.

Green Heron In Prairie Potholes Population Forecast

If the recent trend holds, Green Heron in Prairie Potholes is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±83.6%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.03Projected 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 →
0.00–0.0995% 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 →
±83.6%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 Prairie Potholes is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±83.6%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.030.000.09
20260.030.000.09
20270.030.000.09
20280.030.000.09
20290.030.000.09

Routes In Prairie Potholes

Routes recording Green Heron in Prairie Potholes.
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 →
Big StoneMINNESOTA42011
ChokioMINNESOTA32005
WashingtonIOWA21993
GarnerIOWA21992
CourtlandMINNESOTA22023
Redwood FallMINNESOTA21980
TenneyMINNESOTA21996
Lake BronsonMINNESOTA21979
FranklinMINNESOTA22021
EmeradoNORTH-DAKOTA22007
LennoxSOUTH-DAKOTA22012
WilmotSOUTH-DAKOTA22007
CondeSOUTH-DAKOTA21984
PantherIOWA11999
KanawhaIOWA11989
ZearingIOWA11994
ScrantonIOWA11983
ClareIOWA11976
TitonkaIOWA11975
HartlandMINNESOTA12012
HuntleyMINNESOTA12017
ChandlerMINNESOTA12023
ArlingtonMINNESOTA12004
MaynardMINNESOTA12015
DawsonMINNESOTA11981

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