- 5.1–5.9 in
- 7.1–7.9 in
- 0.7–1 oz
- Although territorial, the Seaside Sparrow often feeds long distances from the space it defends around its nest. In the tidal zone where it lives, nesting and feeding areas often are widely separated.
- The Seaside Sparrow is divided into several different subspecies that look subtly different. The two most distinct forms, the endangered "Cape Sable" Seaside Sparrow and the extinct "Dusky" Seaside Sparrow were once considered separate species. The "Cape Sable" Seaside Sparrow has dark streaks on a white chest and is the palest form. The "Dusky" Seaside Sparrow was the darkest form, with a blackish back and heavy dark chest streaks.
Salt marshes, especially spartina grass, rushes, and tidal reeds; "Cape Sable" Seaside Sparrow in marsh prairie.
Seeds, insects, spiders, marine invertebrates.
- Clutch Size
- 2–5 eggs
- Egg Description
- Bluish white to grayish white, speckled and blotched with shades of brown, often more heavily on larger end.
- Condition at Hatching
Open cup of grass stems and blades, lined with finer grass blades and sometimes built up on sides to form partial covering.
Walks on ground and gleans prey from surrounding vegetation; probes with bill in mud.
Common overall, but some populations vulnerable. "Cape Sable" Seaside Sparrow of southern Florida is severely endangered and is on the 2014 State of the Birds Watch List, which lists species most in danger of extinction without significant conservation action. "Dusky" Seaside Sparrow went extinct in the 1980s.
- Post, W., and J. S. Greenlaw. 1994. Seaside Sparrow (Ammodramus maritimus). In The Birds of North America, No. 127 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologistsâ€™ Union.