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Species · Nevada · BBS 2026 Release · 1966–2025

Black-chinned Sparrow Population Trend in Nevada

All statesArid-land birds

Black-chinned Sparrow in Nevada has declined: down 42% on the route-weighted index since 1998.

-42%Since 1998TrendPercent 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 →
4Routes In StateSurvey 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 Black-chinned Sparrow Trends in NevadaNotable 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 Black-chinned Sparrow in Nevada. See the full index history below.

Black-chinned Sparrow Population Forecast in Nevada

If the recent trend holds, Black-chinned Sparrow in Nevada is projected to fall about 68% by 2030 — from 0.33 in 2025 to a central estimate of 0.11 (95% range 0.00–0.37). A 5-year backtest shows a typical error of ±106%, with 80% of held-out values landing inside the 95% band.

-68%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 →
0.00–0.3795% 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 →
±106%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, Black-chinned Sparrow in Nevada is projected to fall about 68% by 2030 — from 0.33 in 2025 to a central estimate of 0.11 (95% range 0.00–0.37). A 5-year backtest shows a typical error of ±106%, with 80% of held-out values landing inside the 95% band.19962030
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 →
20260.120.000.39
20270.120.000.39
20280.110.000.38
20290.110.000.38
20300.110.000.37

Black-chinned Sparrow Survey Routes in Nevada

Routes recording Black-chinned Sparrow in Nevada.
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 Vally720251996
Nelson520101996
Dobbin Creek420142004
Willis120031997

Black-chinned Sparrow Population Trend in Other States

arizonacaliforniacoloradonew-mexicotexasutah

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