Saving the Imperiled Saltmarsh Sparrow

This soft-voiced, promiscuous bird ekes out a living in tidal marshes. Even in the best circumstances, nesting on ground that floods every month at peak high tide is a risky affair. Add storm surges, water pollution, land development and global warming, and now the tiny saltmarsh sparrow is in big trouble.

Along its breeding range, from midcoast Maine to Virginia, it faces shrinking habitat, says Wenley Ferguson of the Rhode Island-based nonprofit Save the Bay. Previously, slight sea level rises were offset by expansion of the saltmarshes; driven by climate change, recent sea level increases are inundating marshlands faster than they’re expanding. The saltmarsh sparrow population was just 50,000 a decade ago and has declined 9 percent annually. At this rate, experts say, the species will be extinct by 2050.

So conservationists are hurrying to help. Ferguson and volunteers have been digging shallow ditches in saltmarshes to drain excess water; displaced soil is turned into mounds to lure sparrows to higher ground. Others have tried widening tidal culverts or placing coconut coir logs near marsh boundaries to contain sediment.

As long as the wetlands don’t disappear entirely, there’s reason to hope the frisky saltmarsh sparrow, with a hand from us, will find a way. One of its quirks is that males and females breed with multiple partners. Promiscuity may be an adaptation to the danger of a nest full of eggs being destroyed by a peak high tide; mating opportunistically lets adults start over right away before a breeding season ends. “There’s this whole ‘free love’ thing happening in the marsh,” says Kate Ruskin, a University of Maine researcher and member of the Saltmarsh Habitat and Avian Research Program (SHARP). “It’s a really interesting story about ecology, evolution and how creatures become specialized to their habitats.”