BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Great Egret In Great Basin

All regionsGreat BasinWetland birds

Great Egret in Great Basin has fallen sharply: down 59% on the route-weighted index since 1974.

-59%Since 1974TrendPercent 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 →
46Routes 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 →
52YearsYears 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 →

Great Egret has fallen sharply in Great Basin: down 59% on the route-weighted index since 1974.

Great Egret In Great Basin Population Forecast

If the recent trend holds, Great Egret in Great Basin is projected to rise about 110% by 2029 — from 0.27 in 2024 to a central estimate of 0.57 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±239.7%, with 80% of held-out values landing inside the 95% band.

+110%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 →
0.57Projected 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 →
0.00–1.295% 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 →
±239.7%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 Egret in Great Basin is projected to rise about 110% by 2029 — from 0.27 in 2024 to a central estimate of 0.57 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±239.7%, with 80% of held-out values landing inside the 95% band.19722029
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 →
20250.570.001.2
20260.570.001.2
20270.570.001.2
20280.570.001.2
20290.570.001.2

Routes In Great Basin

Routes recording Great Egret in Great Basin.
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 →
DorrisCALIFORNIA442019
Fish LakeOREGON252022
Modoc PointOREGON172018
Moses LakeWASHINGTON172021
Modoc Point 2OREGON162024
LikelyCALIFORNIA142024
Honey LakeCALIFORNIA82019
Carson RiverNEVADA72005
Trout CreekOREGON52000
Clear Lk ResCALIFORNIA41999
HikoNEVADA42023
Warner VallyOREGON42023
MacdoelCALIFORNIA32018
PrincetonOREGON31985
Harney LakeOREGON32024
Ruby Valley 2NEVADA22021
UmatillaOREGON22022
MerrillOREGON22018
Catlow RimOREGON22016
Scootney ReservoirWASHINGTON22024
NubieberCALIFORNIA12005
IngallsCALIFORNIA11992
Crowley LakeCALIFORNIA12022
Davis CreekCALIFORNIA12014
MadelineCALIFORNIA12021

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