Every picture tells a story - or two - in a new exhibit in Niantic.

In "The Seasons of a Marsh," paintings of Barn Island by Roxanne Steed of Mystic hang alongside four essays by Steed's friend and Day staff writer and environmental reporter Judy Benson, a frequent visitor to the preserve, both professionally and recreationally. Where Steed's images depict the vivid palette every season unveils on the preserve, Benson's words add context, history and her own natural color to the viewer's experience of the unique landscape. The 28 paintings in the exhibit show Barn Island between September 2012 and the summer of 2014.

"The Seasons of a Marsh" is on display at the Artisan Framing & Gallery, 293 Main St., Niantic. It opens on Friday with a reception from 5 to 8 p.m., and runs through Oct. 24. For more information, call (860) 739-2286.

Benson's essays appear here.

I

Wild crashing surf and mountaintop views stimulate the eyes with nature's drama and power, but here in southeastern Connecticut, our visual jewels deliver a different kind of optical therapy. Barn Island in Stonington is such a jewel, offering something more like an enlivening massage for the eyes that echoes through that overactive organ between the ears, cleansing the mind with a wash a quiet beauty.

With a curious sounding name that probably made sense to our ancestors - it's not an island, but there was once a large barn visible for miles, a landmark from land and sea - this 1,024-acre preserve has as its centerpiece vast tidal marshes that meet Long Island Sound between Wequetequock Cove and Little Narragansett Bay. A favorite trail for hikers, dog walkers, bird watchers and cross-country skiers crosses atop manmade dikes that choked off natural tidal flows and nearly killed the marsh ecosystem, until restoration beginning in the 1970s returned the marine hydrology. Now, a system of culverts carries the high tides that meander through the saltmeadow cord grass of the low marshes at the edge of Little Narragansett Bay, and wander into the smooth cord grass of the high marsh. Differences in the salt-water to fresh-water balance distinguish the low from the high marsh, with the varieties of grasses uniquely adapted to each. The subtle rise in elevation also means a great deal to creatures like the threatened saltmarsh sharp-tailed sparrow that depend on the few places like Barn Island left for nesting.

Once, 80 percent of Connecticut's coastline resembled Barn Island, with the sea seeping into the land and the land seeping down from forests and fields over a spongy, transitional landscape. Now, the few remaining marshes are left for us to protect and cherish, saved after humans finally came to realize the vital role these ecosystems play as fish nurseries, flood buffers and picnic grounds for shore birds. Even on winter days, egrets and great blue herons often can be seen in the Barn Island marshes, building up the suspense as the silently stalk a crab or mummichog for an audience of passing nature lovers, until the big birds strike and swallow.

Over the decades, Barn Island has escaped and recovered from misguided human meddling - from unnaturally straight ditches dug for mosquito control in the 1930s and 1940s to a proposal to turn it into a golf course. Today, though state ownership protects Barn Island from development, a different kind of threat looms. As climate change causes the seas to rise, Barn Island and other marshes are migrating landward or being lost entirely. The grasses that serve as the foundation plants of these coastal prairies accept regular intervals of high and low tides, but some of the plants and animals can't survive with too much salt water for too long. At Barn Island, scientists have been documenting the landward creep of saltmeadow cord grass into areas once dominated by the less salt-tolerant smooth cord grass and black grass. The smooth cord grass and black grass, in turn, is inching into an upland forest, where a stand of black gum trees is retreating at the sting of salt water in the soil.

After the third right-hand fork in the main trail, walkers come to a scene that is one of the most striking tangible examples of the local effects of rising sea levels, though its significance wouldn't be apparent to the untrained eye. There, in the marsh, a few yards from a stand of trees and shrubs, is an old stone wall enclosing not a pasture or copse, but a plot of marsh grass indistinguishable from the marsh grass that surrounds it. The only way to reach to wall is to traipse across the wet marsh, the ooze gulping as feet sink and pull up, sink and pull up. The wall dates back some 200 years or more. When that long-ago farmer built it, this part of Barn Island was solid ground, not marsh.

II

Among painting genres, plein air landscapes express a singular vision fostering understanding and appreciation for the natural world and the human relationship to it. The perspective might be seen as the opposite of a still life - of inanimate objects, plucked flora and static fauna deliberately collected and arranged by the artist apart from the larger world. Instead, a plein air work depicts an ever-changing environment at a particular point in time, capturing an ephemeral moment of the artist's experience of a place that is alive and responding in myriad ways to the forces of nature and man.

At Barn Island, day-to-day changes in weather, light and tidal conditions keep the marshes stylishly dressed for every occasion. But a longer view is required to fully grasp the beauty and significance of these scenes. The first of the several parcels that make up what are now Barn Island were acquired by the state in the 1940s primarily for hunting, and early restoration efforts focused mainly on trying to bring back declining populations of waterfowl. Still officially named the Barn Island Wildlife Management Area, it now supports multiple recreational uses in addition to hunting, and over the years restoration projects broadened beyond birds to the entire marsh ecosystem. In the late 1970s, scientists from the state Department of Environmental Protection began working with botanists at Connecticut College to restore the marsh hydrology and reconnect the upland marsh to Little Narragansett Bay and Long Island Sound. Culverts were dug through the manmade dikes that had cut off the natural tidal flows.

"When we first started we didn't even know if it would work," recalled Scott Warren, botany professor emeritus at Connecticut College. "It took a dozen years for the marsh plants to come back, and about 20 to 25 years to bring it back to a fully functioning marsh. Now it seems to be going gangbusters."

Ron Rozsa, retired state coastal ecologist, helped lead the restoration of 70 marshes along the Connecticut coast during his career, but counts Barn Island among his proudest achievements. He and Prof. Warren continue to work on conservation and research projects there, confident that Barn Island still has much to teach them, and that it shouldn't be taken for granted.

Rozsa recalled a recent find while exploring one of the "seepage zones" at Barn Island. That's one of the forests bordering the marsh that's nourished by fresh water discharging from underground, surviving on a delicate edge where the tidal marine waters creep landward. There, he discovered the remnants of a barge that he deduced washed up during Hurricane Carol in 1954.

"Barn Island is still giving up secrets," he said.

III

While land and sea are often thought of as separate environments, the signature feature of Barn Island is the horizontal expanse where the two are intertwined. A vertical human figure standing on the main trail, looking south across the gently undulating stretch of grass and water to Little Narragansett Bay, then north across the high mash to the upland forest, can't help but comprehend anew in some deep corner of her being the interconnectedness of nature.

The 300 acres of marshes at Barn Island embody the transition between solid ground and salt water, where the daily wash of high tides and low tides amongst the green blades renders the usual categories of natural features indistinguishable. But what makes Barn Island a truly special place is that its marshes are surrounded by 700 acres of forest.

"It's the largest marsh in the Northeast with an undeveloped upland," said Scott Warren, professor emeritus of botany at Connecticut College. "If you want to protect marshes, you need to protect the upland that abuts them."

The upland forest filters the fresh surface and groundwater flowing into the marshes, protecting it from excesses of nitrogen and other nutrients that have polluted other marshes. With research dating back to the 1940s and a successful restoration project considered a model, Barn Island maintains a storied role in environmental science.

For Warren, who first began going to Barn Island as a young botanist in 1972, it has never lost its appeal.

"The breathtaking view and peacefulness is really pretty special," Warren said.

IV

With egrets, ibis, great blue herons, ducks and rails often seen in its marshes, even casual birdwatchers can easily understand why the National Audubon Society has designated Barn Island as a "Globally Significant Bird Area." The marshes also support two small songbirds, the saltmarsh sharp-tailed sparrow and the seaside sparrow.

"Barn Island is one of the state's most important sites for coastal birds," said Chris Ephick, professor of ecology and evolutionary biology at the University of Connecticut who has been researching the impact of rising sea levels on the saltmarsh sharp-tailed sparrows at Barn Island.

But the diversity of the bird species is just one of the reasons Barn Island was named one of 33 Long Island Sound Stewardship Sites in 2009, a designation given to the most significant areas on both the Connecticut and New York sides of the estuary. The marshes and forests of Barn Island have drawn people for centuries, from Native Americans to colonial farmers and fishermen to modern outdoorsmen and researchers. Its various habitats, from salt and brackish marshes to coastal woodlands, sandy beach, intertidal flats and a rare sea-level fen, support rare plants and animals, including 25 federal or state-listed endangered, threatened or special-concern species. The conservation value of the 1,024 acres owned by the state are further enhanced by two adjacent parcels protected by the Avalonia Land Conservancy.

Barn Island "has contributed greatly to our knowledge of the ecology and restoration of marsh ecosystems," Elphick said.

j.benson@theday.com

Twitter: @BensonJudy