BirdAnalyst
Species · BCR 19 · BBS 2025 Release · 1966–2024

Great Blue Heron In Central Mixed Grass Prairie

All regionsCentral Mixed Grass PrairieWetland birds

Great Blue Heron in Central Mixed Grass Prairie has surged: up 191% on the route-weighted index since 1969.

+191%Since 1969TrendPercent 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 →
121Routes 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 →
57YearsYears 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 increasecomputed 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 →

Great Blue Heron has surged in Central Mixed Grass Prairie: up 191% on the route-weighted index since 1969.

Forecast

If the recent trend holds, Great Blue Heron in Central Mixed Grass Prairie is projected to stay roughly flat through 2029, near 1.1 (95% range 0.41–1.7). A 5-year backtest shows a typical error of ±10.7%, with 100% of held-out values landing inside the 95% band.

+8%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 →
1.1Projected 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 →
0.41–1.795% 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 →
±10.7%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, Great Blue Heron in Central Mixed Grass Prairie is projected to stay roughly flat through 2029, near 1.1 (95% range 0.41–1.7). A 5-year backtest shows a typical error of ±10.7%, 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 →
20251.00.401.7
20261.00.401.7
20271.00.401.7
20281.00.411.7
20291.10.411.7

Routes In Central Mixed Grass Prairie

Routes recording Great Blue Heron in Central Mixed Grass Prairie.
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 →
CoopertonOKLAHOMA112024
JetOKLAHOMA92024
WeinertTEXAS81994
MertzonTEXAS82012
ElginOKLAHOMA72016
BerwetKANSAS52024
ArthurNEBRASKA52023
Crescent LkNEBRASKA52017
Shields 2TEXAS52023
PhillipsburgKANSAS42022
GrimesOKLAHOMA42022
CoatsKANSAS32009
AlbertKANSAS32024
HanoverKANSAS32023
GoveKANSAS32011
CookietownOKLAHOMA32002
DouglasOKLAHOMA32022
ChesterOKLAHOMA31987
HollisOKLAHOMA32024
EldoradoTEXAS31983
HawleyTEXAS32024
WilliamsTEXAS32024
WellingtonKANSAS22024
ColdwaterKANSAS22019
AshlandKANSAS22021

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