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

Bobolink In Great Basin

All regionsGreat BasinGrassland birds

Bobolink in Great Basin has risen sharply: up 54% on the route-weighted index since 1977.

+54%Since 1977TrendPercent 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 →
19Routes 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 →
48YearsYears 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 →

Bobolink has risen sharply in Great Basin: up 54% on the route-weighted index since 1977.

Bobolink In Great Basin Population Forecast

If the recent trend holds, Bobolink in Great Basin is projected to rise about 74% by 2029 — from 0.06 in 2024 to a central estimate of 0.10 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±99.5%, with 100% of held-out values landing inside the 95% band.

+74%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 →
0.10Projected 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 →
0.00–0.2495% 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 →
±99.5%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, Bobolink in Great Basin is projected to rise about 74% by 2029 — from 0.06 in 2024 to a central estimate of 0.10 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±99.5%, with 100% of held-out values landing inside the 95% band.19742029
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 →
20250.100.000.24
20260.100.000.24
20270.100.000.24
20280.100.000.24
20290.100.000.24

Routes In Great Basin

Routes recording Bobolink 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 →
NighthawkWASHINGTON92016
Fish LakeOREGON62024
JosephOREGON42016
BatesIDAHO32018
AlmoIDAHO32000
SpringfieldIDAHO22004
PocatelloIDAHO21996
PrincetonOREGON21985
Goose Creek Mtn.UTAH22023
CedarvilleCALIFORNIA12016
BakerIDAHO12024
LeadoreIDAHO11981
CratersIDAHO11989
Dougal ResIDAHO11993
Cedar HillIDAHO12019
RanchograndeNEVADA12024
BlitzenOREGON11987
Timpie SpgUTAH11988
TonasketWASHINGTON12013

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