A tiny sparrow that lives in salt marshes from Maine to Virginia could be the new “poster child” for our changing coastal habitat. Experts say rising sea levels make the bird’s future uncertain, and it may spell the first sign of danger to an entire ecosystem.
A salt marsh isn’t very homey. There are no trees, and the short, stubbly bushes don’t offer much cover from predators, like hawks, for a small bird like the saltmarsh sparrow. Plus, everything’s covered in salty sea water.
University of Connecticut graduate student Samantha Apgar says, “Flooding is an essential part of marshes. It’s just a way of life daily.”
Apgar trudges through a salt marsh at Connecticut’s Hammonasset State Park. Every step could be dry ground or a mud puddle that sucks you in up to your knees.
“Oops, and I’m falling in!” Apgar steadies herself and says this isn’t an easy place for any animal. “Which is why there are only a couple specialist species that live and breed, and spend most of their life cycles in this ecosystem.”
The saltmarsh sparrow is one of them because it keeps to the ground. It’s lightweight and scurries around on big feet that keep it from sinking in the mud. And it’s not easy to spot.
“Sometimes they will come up, too, if you just go, ‘Pfft, pfft, pfft!’”
Patrick Comins with Audubon Connecticut tries to lure one out for a good look. A bird pops up from the bushes, then quickly pops back down again.
“Yep. That was a saltmarsh, I bet. We don’t know why they pop up when you do that, but they do.”
He says the bird rarely flies any higher than the top branches.
“If you see a small sparrow just pop up out of the salt marsh, fly a little ways, and then drop back down again, it’s probably a saltmarsh sparrow.”
And that keep-your-head-down strategy is what puts saltmarsh sparrows at risk because they build their nests on the ground. Samantha Apgar says they only have a small window of time to get their eggs hatched and chicks out of the nest before the tide comes in and washes them away.
“As the high tides creep on each end of that short window, there won’t be a time for them to fledge these chicks. So it’s really spelling disaster for the species.”
Apgar, along with University of Connecticut biologist Chris Elphick, looked at how sea level rise will affect the salt marshes over the next century. Elphick says the saltmarsh sparrow may not have more than 50 years to survive in its habitat. But the little bird is only the first sign of trouble.
“It acts kind of like the proverbial canary in the coal mine in that it’s an indicator of what’s gonna happen to the rest of the system, all of the other species.”
That includes at least four other birds that live in the marsh, like the seaside sparrow and clapper rail. And there will be nowhere left for them to go because much of the land here along the coast has been developed. There are a few suggestions being bantered about on how to provide a place for the birds to lay their eggs. But none of them are simple – for instance, artificial islands that would float in the tide like tiny arks.
You can learn more about the saltmarsh sparrow and other birds of the salt marsh at Audubon.