Saltmarsh and Seaside Sparrows. 7/7/2024

Both Saltmarsh and Seaside Sparrows are denizens of coastal saltmarshes where they breed from Maryland north to New Hampshire. Both species build their nests above the high tide zone, but Saltmarsh Sparrows seem to build theirs closer to the high tide mark making the nest very susceptible to flooding at astronomical tides. In fact, Saltmarsh Sparrows time egg-laying to avoid astronomical high tides but poor timing or very high tides can cause the nests to flood. The eggs, however, are able to survive being immersed for short periods. Male Saltmarsh Sparrows do not develop territories or help in the rearing of young and are somewhat polygamous perhaps because of the high likelihood of nest failure. Habitat loss of our saltwater marshes and rising sea levels gravely threaten these sparrows. Seaside Sparrows build their nests at a slightly higher level, and the male participates in the rearing of young so this species is not as threatened although habitat loss is still a huge concern. I was able to see Saltmarsh Sparrow at Allen's Pond Wildlife Sanctuary in Westport, MA and both species on the Ninigret Mudflats in Charlestown, RI this month. All appeared to be nesting and raising young. The Saltmarsh Sparrow is above and the Seaside below.