BirdAnalyst
Species · BBS 2026 Release · 1966–2025

Black-throated Sparrow Population Analysis

PasserellidaeArid-land birdsAmphispiza bilineata

Black-throated Sparrow has held roughly steady: down 7% on the route-weighted index since 1969.

-7%Since 1969TrendPercent 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 →
502RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Black-throated Sparrow

The Black-throated Sparrow (Amphispiza bilineata) is a North American member of the New World Sparrows (Passerellidae). In this analysis it is grouped with the arid-land birds.

Size
4.5–7.5 in long (12–19 cm) — a small songbird (typical for the family)
Habitat
Deserts, dry scrub and brushland of the Southwest.
Diet
Seeds, insects and cactus fruit of arid-land plants.
Range
Recorded on 502 Breeding Bird Survey routes across 11 states, most concentrated in the Great Basin.
Family
Passerellidae · Arid-land birds

Notable Black-throated Sparrow TrendsNotable 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-throated Sparrow. See the full index history below.

Black-throated Sparrow Population Forecast

If the recent trend holds, Black-throated Sparrow is projected to stay roughly flat through 2030, near 1.5 (95% range 0.66–2.3). A 5-year backtest shows a typical error of ±16.7%, with 100% of held-out values landing inside the 95% band.

-4%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 →
1.5Projected 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 →
0.66–2.395% 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 →
±16.7%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, Black-throated Sparrow is projected to stay roughly flat through 2030, near 1.5 (95% range 0.66–2.3). A 5-year backtest shows a typical error of ±16.7%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20261.50.652.3
20271.50.652.3
20281.50.662.3
20291.50.662.3
20301.50.662.3

Where the Black-throated Sparrow Is Detected

BBS routes recording Black-throated Sparrow, sized by most recent count.

Black-throated Sparrow Population Trend by State

Black-throated Sparrow population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Arizona-27%197076
California-54%197078
Colorado-0%198017
Idaho-62%19898
Nevada-39%197052
New Mexico+55%197061
Oklahomainsufficient datan/a1
Oregon+106%197124
Texas-69%1969102
Utah14×197181
Washingtoninsufficient datan/a2

Black-throated Sparrow Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Black-throated Sparrow population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Great Basin-59%1970122
Southern Rockies / Colorado Plateau-43%1970104
Shortgrass Prairie-93%196923
Central Mixed Grass Prairie-65%196911
Edwards Plateau+25%196914
Oaks and Prairies-63%19697
Coastal California-83%197217
Sonoran and Mojave Deserts-28%197084
Sierra Madre Occidental-62%197027
Chihuahuan Desert-35%196956
Tamaulipan Brushlands-94%196925

Black-throated Sparrow Conservation Status

Our route-weighted index shows it down about 7% since 1969.

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.