BirdAnalyst
Species · BCR 9 · BBS 2026 Release · 1966–2025

Lucy's Warbler In Great Basin

All regionsGreat BasinArid-land birds

Lucy's Warbler in Great Basin has surged: up 475% on the route-weighted index since 1997.

+475%Since 1997TrendPercent 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 →
3Routes 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 →
18YearsYears 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 Lucy's Warbler in Great Basin. See the full index history below.

Lucy's Warbler In Great Basin Population Forecast

If the recent trend holds, Lucy's Warbler in Great Basin is projected to fall about 31% by 2030 — from 0.15 in 2025 to a central estimate of 0.11 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±90.5%, with 20% of held-out values landing inside the 95% band.

-31%Change by 2030TrendPercent 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 →
0.11Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.2195% 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 →
±90.5%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, Lucy's Warbler in Great Basin is projected to fall about 31% by 2030 — from 0.15 in 2025 to a central estimate of 0.11 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±90.5%, with 20% of held-out values landing inside the 95% band.19692030
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 →
20260.100.000.20
20270.100.000.21
20280.100.000.21
20290.100.000.21
20300.110.000.21

Routes In Great Basin

Routes recording Lucy's Warbler 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 →
Meadow VallyNEVADA202025
HikoNEVADA32022
NewcastleUTAH12016

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.