Seaside Sparrow
Seaside Sparrow has fallen sharply: down 55% on the route-weighted index since 1968.
About the Seaside Sparrow
The Seaside Sparrow (Ammospiza maritima) is a North American member of the New World Sparrows (Passerellidae). In this analysis it is grouped with the wetland birds.
- Size
- 4.5–7.5 in long (12–19 cm) — a small songbird (typical for the family)
- Habitat
- Marshes, ponds, lakeshores and other freshwater wetlands.
- Diet
- Aquatic invertebrates, small fish, frogs and plant matter.
- Range
- Recorded on 46 Breeding Bird Survey routes across 12 states, most concentrated in the New England / Mid-Atlantic Coast.
- Family
- Passerellidae · Wetland birds
Notable Seaside Sparrow Trends
No notable trend signals for Seaside Sparrow. See the full index history below.
Seaside Sparrow Population Forecast
If the recent trend holds, Seaside Sparrow is projected to stay roughly flat through 2029, near 0.05 (95% range 0.02–0.08). A 5-year backtest shows a typical error of ±135.9%, with 20% of held-out values landing inside the 95% band.
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.05 | 0.02 | 0.08 |
| 2026 | 0.05 | 0.02 | 0.08 |
| 2027 | 0.05 | 0.02 | 0.08 |
| 2028 | 0.05 | 0.02 | 0.08 |
| 2029 | 0.05 | 0.02 | 0.08 |
Where the Seaside Sparrow Is Detected
BBS routes recording Seaside Sparrow, sized by most recent count.
Seaside Sparrow Population Trend by State
| Alabama | insufficient data | n/a | 2 |
| Delaware | +742% | 1969 | 10 |
| Florida | -59% | 1975 | 6 |
| Louisiana | 19× | 1973 | 7 |
| Maryland | +44% | 1968 | 3 |
| Massachusetts | insufficient data | n/a | 1 |
| New Jersey | insufficient data | n/a | 2 |
| New York | insufficient data | n/a | 2 |
| North Carolina | insufficient data | n/a | 2 |
| South Carolina | insufficient data | n/a | 1 |
| Texas | +145% | 1994 | 7 |
| Virginia | -71% | 1995 | 3 |
Seaside Sparrow Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
| Southeastern Coastal Plain | -96% | 1968 | 9 |
| New England / Mid-Atlantic Coast | +116% | 1968 | 21 |
| Gulf Coastal Prairie | +80% | 1973 | 14 |
Seaside Sparrow Conservation Status
Our route-weighted index shows it down about 55% since 1968.
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.