WatchList Species Account for Seaside Sparrow (Ammodramus maritima)

Qualifies for the list as a Red List Species

Photo: © Bill Hubick

Occurring in relatively small, localized populations, the Seaside Sparrow inhabits salt and brackish marshes along the coast from Maine through Texas. In winter the northern populations are short distance migrants, and most spent the nonbreeding season south of Delaware. Historical destruction of these marshes has doubtlessly diminished populations of this bird. Although subspecific structuring within this species needs revision, one described subspecies, the Dusky Seaside Sparrow of Atlantic coastal Florida became extinct in the 1980s as a result of habitat destruction, marsh draining and impoundment, and mosquito control, while another, the Cape Sable race that inhabits the Everglades, is severely imperiled, largely through manipulation of water levels. The various subspecies of Seaside Sparrows vary considerably in the color of their plumage, from grayish-, yellowish- and greenish-olive to brownish black or even black.

Overall, other populations are currently stable (as considered on the basis of very poor monitoring data), but vulnerable to a variety of threats. Outright conversion of their habitat seems to have ceased, but their habit of building nests just above high tide line exposes them to losses from storms and oil spills and other changes which affect water levels. Such changes also affect favored foraging patches such as mud flats and mud pools. Exotic invasives are a problem, but the biggest threat is posed by rising sea levels caused by global warming. Salt marshes can no longer march backward with a rising ocean as so much of the land behind them is developed. Saltmarsh and the coastal populations of Nelson’s Sharp-tailed Sparrows face this same threat.