Lark Bunting
Lark Bunting has fallen sharply: down 70% on the route-weighted index since 1969.
About the Lark Bunting
The Lark Bunting (Calamospiza melanocorys) 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 553 Breeding Bird Survey routes across 17 states, most concentrated in the Badlands and Prairies.
- Family
- Passerellidae · Grassland birds
Notable Lark Bunting Trends
Lark Bunting has fallen sharply in surveyed states: down 70% on the route-weighted index since 1969.
Lark Bunting Population Forecast
If the recent trend holds, Lark Bunting is projected to fall about 13% by 2029 — from 2.7 in 2024 to a central estimate of 2.4 (95% range 0.00–5.1). A 5-year backtest shows a typical error of ±26.4%, with 100% of held-out values landing inside the 95% band.
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 2.7 | 0.00 | 5.5 |
| 2026 | 2.6 | 0.00 | 5.4 |
| 2027 | 2.5 | 0.00 | 5.3 |
| 2028 | 2.4 | 0.00 | 5.2 |
| 2029 | 2.4 | 0.00 | 5.1 |
Where the Lark Bunting Is Detected
BBS routes recording Lark Bunting, sized by most recent count.
Lark Bunting Population Trend by State
| Arizona | insufficient data | n/a | 2 |
| California | insufficient data | n/a | 1 |
| Colorado | -86% | 1970 | 78 |
| Idaho | -96% | 1996 | 11 |
| Iowa | insufficient data | n/a | 3 |
| Kansas | -97% | 1969 | 31 |
| Minnesota | insufficient data | n/a | 3 |
| Missouri | insufficient data | n/a | 1 |
| Montana | -69% | 1970 | 66 |
| Nebraska | -74% | 1969 | 54 |
| New Mexico | -67% | 1970 | 28 |
| North Dakota | -99% | 1969 | 42 |
| Oklahoma | +53% | 1969 | 10 |
| South Dakota | -83% | 1969 | 54 |
| Texas | +357% | 1969 | 31 |
| Utah | -93% | 1996 | 22 |
| Wyoming | -69% | 1970 | 116 |
Lark Bunting Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
| Great Basin | -64% | 1995 | 19 |
| Northern Rockies | -34% | 1970 | 83 |
| Prairie Potholes | -89% | 1969 | 74 |
| Southern Rockies / Colorado Plateau | -98% | 1970 | 45 |
| Badlands and Prairies | -79% | 1969 | 126 |
| Shortgrass Prairie | -73% | 1969 | 124 |
| Central Mixed Grass Prairie | -95% | 1969 | 63 |
| Chihuahuan Desert | -78% | 1973 | 8 |
Lark Bunting Conservation Status
Our route-weighted index shows it down about 70% 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.