BirdAnalyst
Species · BBS 2025 Release · 1966–2024

LeConte's Sparrow

PasserellidaeGrassland birdsAmmospiza leconteii

LeConte's Sparrow has declined: down 45% on the route-weighted index since 1969.

-45%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 →
120RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57Years 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 LeConte's Sparrow

The LeConte's Sparrow (Ammospiza leconteii) is a North American member of the New World Sparrows (Passerellidae). In this analysis it is grouped with the grassland birds.

Size
4.5–7.5 in long (12–19 cm) — a small songbird (typical for the family)
Habitat
Open grasslands, prairie, pasture and hayfields.
Diet
Seeds and insects gathered from grasses and the ground.
Range
Recorded on 120 Breeding Bird Survey routes across 6 states, most concentrated in the Boreal Hardwood Transition.
Family
Passerellidae · Grassland birds

Notable LeConte's 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 LeConte's Sparrow. See the full index history below.

LeConte's Sparrow Population Forecast

If the recent trend holds, LeConte's Sparrow is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±568.5%, with 0% of held-out values landing inside the 95% band.

n/aChange 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 →
0.03Projected 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 →
0.00–0.0795% 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 →
±568.5%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, LeConte's Sparrow is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±568.5%, with 0% of held-out values landing inside the 95% band.19672029
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 →
20250.030.000.07
20260.030.000.07
20270.030.000.07
20280.030.000.07
20290.030.000.07

Where the LeConte's Sparrow Is Detected

BBS routes recording LeConte's Sparrow, sized by most recent count.

LeConte's Sparrow Population Trend by State

LeConte's 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 →
Michigan-64%19719
Minnesota+170%196940
Montanainsufficient datan/a3
North Dakota-78%197035
South Dakotainsufficient datan/a4
Wisconsin-76%196929

LeConte's Sparrow Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

LeConte's 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 →
Prairie Potholes-79%197045
Boreal Hardwood Transition-25%196949
Prairie Hardwood Transition-24%196918

LeConte's Sparrow Conservation Status

Our route-weighted index shows it down about 45% since 1969. Grassland birds are North America's steepest-declining group, down roughly 50% since 1970 as prairie and pasture were lost.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.