Editor’s Note (August 2016): Maps, rich media, and text have been updated to reflect a taxonomic change/split for this species. This species account is still being edited and may contain content from an earlier version of the account.
The Saltmarsh Sparrow is a secretive and highly localized species largely restricted as a breeding bird to wet meadows, edges of freshwater marshes, and salt marshes in recently deglaciated regions of Atlantic coastal North America. It occurs along the northeast Atlantic Coast.
Across its range, this sparrow is non-territorial and promiscuous, and only females provide parental care. Males occupy large overlapping home ranges, and at least in southern populations, the mating relationship features forced copulations by males. Active males engaged in reproduction greatly outnumber fertilizable females. Adult survival of both sexes and breeding success in southern birds are comparable to values observed in marshland and grassland relatives that exhibit biparental care.
Breeding success in many saltmarsh populations seems limited by storms and especially “spring” (high) tides, which often flood nests. The most successful pairs in these populations are those that renest soon after the flood tides of the new moon; the short incubation and nestling periods of this species allow such pairs to fledge their young before the returning flood tides of the full moon.