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

Western Bluebird In Great Basin

All regionsGreat BasinForest birds

Western Bluebird in Great Basin has surged: up 11× on the route-weighted index since 1970.

11×Since 1970TrendPercent 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 →
73Routes 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 →
56YearsYears 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 →

Western Bluebird has surged in Great Basin: up 11× on the route-weighted index since 1970.

Western Bluebird In Great Basin Population Forecast

If the recent trend holds, Western Bluebird in Great Basin is projected to rise about 44% by 2029 — from 0.51 in 2024 to a central estimate of 0.73 (95% range 0.50–0.96). A 5-year backtest shows a typical error of ±44.6%, with 40% of held-out values landing inside the 95% band.

+44%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 →
0.73Projected 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 →
0.50–0.9695% 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 →
±44.6%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, Western Bluebird in Great Basin is projected to rise about 44% by 2029 — from 0.51 in 2024 to a central estimate of 0.73 (95% range 0.50–0.96). A 5-year backtest shows a typical error of ±44.6%, with 40% of held-out values landing inside the 95% band.19682029
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 →
20250.690.460.91
20260.700.470.92
20270.710.480.93
20280.720.490.94
20290.730.500.96

Routes In Great Basin

Routes recording Western Bluebird 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 →
EllensburgWASHINGTON282024
Deep SpringsCALIFORNIA201974
PomeroyWASHINGTON192024
Carson RiverNEVADA132002
Iron GateCALIFORNIA92019
EightmileOREGON91991
HackamoreCALIFORNIA62010
Fall River MillsCALIFORNIA62011
Jericho JunctionUTAH61997
Ewan 2WASHINGTON62023
TionestaCALIFORNIA42021
GiffordIDAHO42016
JoelIDAHO42024
ZumwaltOREGON42005
NewcastleUTAH42022
SelahWASHINGTON42012
MacdoelCALIFORNIA32019
MadelineCALIFORNIA32021
Davis LakeOREGON32013
Modoc Point 2OREGON32024
Pine CreekUTAH32012
Lake ChelanWASHINGTON32024
Turnbull NwrWASHINGTON32023
BodieCALIFORNIA22010
Davis CreekCALIFORNIA22024

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