Our Marshes Are Dying

By DAVID K. FUNKHOUSER

Courant Staff Writer

July 22, 2007

BRANFORD

Peter Banca looked out a window of his Stony Creek home, across his = sloping=20 lawn to the green swath of marsh named for his father, a look of = surprise on his=20 face.

"I had no idea," he said when confronted with the = prediction that=20 the marsh would disappear in a few decades. But he knew the implications = immediately.

Banca marsh has been losing 10 or more feet of its = seaward=20 edge each year to what some scientists call sudden wetland dieback - a = so-far=20 unexplained phenomenon in which marsh grasses die off, leaving mud, = pocked with=20 holes, to wash away with the tide. Even away from the edge, pockets of = marsh=20 grass are fading into barren mud sinks.

The fate of Banca marsh, = and of=20 tidal wetlands around the world, may be tied to rising sea levels and = global=20 warming in intriguing ways. The life of these simple grasses ebbs and = flows to=20 the moon's orbital cycles, to the pressing influence of humans and = perhaps even=20 to a fungus that sails across the Atlantic Ocean on dust storms kicked = up by=20 drought in Africa.

"Sudden dieback" may be a misnomer: For more = than a=20 decade scientists have been uncovering troubling changes in marshes = around the=20 world and trying to decipher the causes. So far, there is no one simple=20 answer.

Along the Gulf Coast of Louisiana, hundreds of thousands = of acres=20 have died off, done in, perhaps, by a combination of drought, heat, = fungus and=20 rising water. Around Hudson Bay, an exploding population of lesser snow = geese=20 has denuded a large area of sub-Arctic wetlands. On Cape Cod, hordes of = purple=20 marsh crabs creep out at night to munch on the cordgrass.

Banca = and his=20 mother, Florence, donated the 5.25-acre marsh next to their home to the=20 University of New Haven a decade ago to protect it from development. = That may=20 turn out to be a moot point if the marsh dies.

"I hope we don't = see that=20 day," said Banca, 58. "But it's going to change the character not only = of my own=20 home, but of the whole Connecticut shoreline."

Losing a marsh = takes away=20 not only nice views, but also a marine nursery for oysters, shrimp, = crabs and=20 fish, and a feeding and nesting area for birds and other = wildlife.

These=20 coastal wetlands trap sediment and filter contaminants from groundwater = and=20 surface water runoff. And marshes serve as a physical barrier between = the sea=20 and the billions of dollars worth of homes, businesses and = infrastructure jammed=20 along the Connecticut shoreline - a shock absorber for flood tides and = storm=20 surges.

This is a front line in the battle over global warming: a = place=20 where the theories about how things change and what might happen come up = against=20 the practical realities of daily life.

The rise in sea level is = expected=20 to accelerate over the coming century due to thermal expansion and = melting=20 land-based ice, according to projections from the U.N.-based = Intergovernmental=20 Panel on Climate Change. It could be a matter of inches or several feet, = depending on what climate models you look at.

Even a few inches = could=20 spell the end of much of the world's coastal wetlands.

"I just = wonder if=20 there's anything we can do, as a society and a nation, to protect = ourselves,"=20 Banca said.

The Coastal Squeeze

Connecticut's salt = marshes=20 have been developing for thousands of years, since glaciers from the = last ice=20 age receded, pouring their melting water into the sea and leaving behind = the=20 basin that is now Long Island Sound.

As long as the sea rose = slowly,=20 marshes could keep pace. Saltwater-tolerant grasses colonized newly = deposited=20 sediment, in turn trapping more sediment and building the marsh. Upper = marsh=20 plants spread inland as the creeping sea pushed at their = borders.

But now=20 the sea may be rising too quickly for marshes to adapt, and manmade = barriers -=20 buildings, parking lots, roads and train tracks - have cut off the = marshes'=20 inland retreat.

At least since the arrival of European colonists, = humans=20 have been fiddling with the marsh equation. They cut ditches to drain = the=20 marshes and cultivated salt marsh hay for their cattle. Wetlands were = filled for=20 development. In the 1930s, federal work projects dug more ditches in an=20 ultimately futile effort to control mosquitoes.

Shoreline = development,=20 from shopping centers to subdivisions, has increased the amount of = fresh,=20 nutrient-rich water running into the marshes. It's also encouraged the = spread of=20 an invasive reed, phragmites. The plant's tall, densely packed stalks = have taken=20 over large areas of high marsh, crowding out native plants and many=20 animals.

A belt of phragmites lines the upper edge of Banca = marsh. Behind=20 it, a former trolley line, now a hiking path, cuts through the marsh. = Farther=20 back, commuter trains whoosh by on the Amtrak line. Roads curve through = clutches=20 of houses mounted on the shore's stony ledge.

From a deck at the = edge of=20 his lawn, Banca can look south past the rocky fingers of Stony Creek, = through=20 the Thimble Islands into the Sound.

"Marshes have kind of come = into their=20 own," Banca said. "In years gone by, they were treated as = dumps."

As=20 Banca tells the story, the grassy rise where his house sits was once a = pile of=20 stone debris from a nearby quarry, where his grandfather, Alexander, = worked.=20 Alexander Banca came to America from Italy in the 1890s and made his = living in=20 stone work and freight hauling on the trolley line.

Alexander's = son,=20 Attilio, befriended a World War I veteran who was convalescing at a home = nearby.=20 Jules Andre Smith was an artist and architect, one of eight men sent by = the U.S.=20 Army to Europe as sketch artists to record life on the front lines. The=20 experience cost him a leg.

Attilio and Smith asked the elder = Banca to=20 sell them the rock dump next to the marsh so they could build a studio = and art=20 gallery. They obviously saw something the grandfather did = not.

"He said,=20 `You're crazy! Why do you want to build down by a swamp?'" Peter Banca = said.=20 Then he gave them the land.

Smith founded The Research Studio in = central=20 Florida, an artists' colony now called the Maitland Art Center. Attilio = Banca=20 ran the gallery in Stony Creek and later in Maitland. When he married in = 1936,=20 he and Florence adapted the studio and gallery as a home, and spent = their=20 summers in Branford and winters in Florida.

In a small stand of = trees=20 just above the marsh sits a rock with a bronze plaque on it: in grateful = memory=20 of Attilio Banca.

Mapping The Marsh

At low tide, = the outer=20 edge of Banca marsh forms a ragged outline. Stems of spartina = alterniflora - the=20 cordgrass that dominates the lower marsh - stick up from a shelf of dark = peat a=20 foot or two above the mud flat.

University of New Haven Professor = Roman=20 Zajac stood in the grass one day this spring, black Wellingtons on his = feet and=20 a yellow, book-size global positioning device in his hand. He waited for = the=20 requisite five satellites to pop onto the GPS screen, then set out to = map the=20 marsh.

Zajac, 58, is a benthic ecologist - he looks at what's on = and in=20 the oceans' sediments. He spent much time as a youth exploring = Hammonasset Beach=20 and Rocky Neck state parks.

He and some of his graduate students = are=20 trying to understand why - and how fast - Banca marsh is eroding. On = this day,=20 Zajac held his GPS reader waist-high and stepped out as far as he could = to trace=20 the edge of the grassy shelf. Every few seconds, the GPS box would beep, = recording a position.

In a healthy marsh, cordgrass holds the = gooey gray=20 sediment together with its roots. Along the edge of Banca marsh, = stretches of=20 bare mud are pockmarked with holes - cavities left behind by dying = cordgrass. In=20 some places, hummocks of peat with tufts of grass still clinging to them = have=20 broken away.

Soon the tide will wash away these chunks and the = bare mud=20 at the edge, and the green marsh will become a mud flat.

The = predicted=20 rise in sea level in response to global warming will certainly hasten = this=20 process.

"Most coastal scientists would agree this is what's = going to=20 happen over the next 10 to 20 years," Zajac said. "How much we lose and = how=20 quickly we lose it becomes the question."

By Zajac's = calculations, about=20 a quarter of the marsh has disappeared. He estimated the 3-acre area he = is=20 mapping will crumble into mud flat in 38 years.

Zajac said the = pace of=20 erosion at Banca may actually have slowed as the crumbling edge reaches = higher=20 marsh, where thicker peat offers more resistance. But another dynamic is = at work=20 there. The dominant high marsh grass is turning brown and = dying.

Using=20 laser-generated images taken from aircraft crisscrossing the marsh, = Zajac and=20 his crew have created precise elevation maps showing where the marsh = appears to=20 be sinking. In these "wet" areas, where the high tide now creeps in more = often,=20 they see high marsh grass dying off.

Zajac is not sure what is = killing=20 off the grasses. Scientists elsewhere are puzzling over the same = problem, and in=20 some cases, they are finding very different answers.

Crabs, = Geese And=20 Snails

Mark Bertness, a marsh ecologist from Brown = University, does=20 not like to speculate about causes.

"Science is not about hunches = and=20 science is not about having a pet hypothesis," Bertness said. "Science = is about=20 figuring it out."

What he figured out on Cape Cod is that large = numbers=20 of the tiny purple marsh crab, sesarma reticulatum, were decimating the = marsh=20 grass.

"Humans are doing something to crank up these crabs," he = said. "I=20 don't know what at this point, it could be over-fishing," which may have = eliminated the crabs' natural predators. "I don't jump to=20 conclusions."

"His preliminary results are astounding," = acknowledged=20 Stephen M. Smith, a plant ecologist at the Cape Cod National Seashore = who is=20 working with Bertness. Smith estimated as much as 12 percent of the = Cape's=20 marshes have died off in recent years.

Smith recently found more=20 surprises. After examining old aerial photographs over the winter, he = and fellow=20 researchers concluded that what they had been calling sudden wetlands = dieback=20 has been going on for at least two decades.

"Perhaps the reason = it's=20 called sudden dieback is because suddenly people noticed it," he=20 said.

Further, some of what they initially thought was low marsh = dying=20 off turns out to be the remnants of higher marsh areas that have been = dying back=20 from their seaward edge. That could be because higher tides have been = flooding=20 them more often with salt water. The same phenomenon has been seen in = the past=20 year at the Hammonasset marshes in Madison.

Bertness sees = parallels to=20 the crab story around Hudson Bay and in the U.S. Southeast. In a 2004 = paper=20 published in American Scientist, Bertness and two colleagues described = how the=20 lesser snow goose has wreaked havoc in the far north.

The geese = breed in=20 the lowlands around Hudson Bay, where they feast on the marsh grass. As = long as=20 there were not too many geese, their eating habits and frequent = defecation,=20 adding nutrients back to the soil, had a positive effect on the=20 grasses.

At one time the geese spent winters mostly grazing in = the=20 coastal marshes of Texas and Louisiana. But starting in the 1960s, the=20 introduction of high-yield crops and nitrogen-based fertilizers in = American=20 agriculture in effect laid out a smorgasbord of rich food for the birds. = The=20 population exploded from an estimated 600,000 to 3 million or = more.

Up=20 north, the impact was devastating. In 10 years, Bertness said, the geese = ate=20 more than 247,000 acres, about a third of the Hudson Bay coastal marsh=20 vegetation.

In the salt marshes of Georgia and South Carolina, = Bertness=20 and colleagues pegged marsh loss to snails. Normally, blue crabs and = other=20 predators eat marsh snails that in turn graze on the cordgrass. The = snails also=20 eat a common fungus that grows on the grass - fusarium. In the absence = of=20 predators - through over-fishing or other changes - the snails can = decimate the=20 marshes, Bertness and his colleagues said.

Fusarium, along with = other=20 factors, is a suspect in recent diebacks of Louisiana's salt marshes. = While=20 Louisiana's marshes have been subsiding and regenerating for a long = time,=20 scientists say the recent diebacks are more extensive and sudden than = previously=20 observed.

Everywhere he looks, Bertness sees the hand of=20 man.

"What I am most alarmed about is that every case we know of = is=20 triggered by human disturbance," he said. "The question is what are the=20 triggers, and what we can do about it?

"It's important that the = general=20 public get a real feel for what could be going on. It's really important = to get=20 this right."

Dust From Africa?

Wade Elmer knows = about=20 fusarium. A plant pathologist at the Connecticut Agricultural Experiment = Station=20 in New Haven, he has been studying the fungus and related plant diseases = in=20 agricultural crops for 20 years.

Now, with a grant from the Long = Island=20 Sound License Plate Fund, he is looking at the marshes. He and two = colleagues=20 slogged around the Banca marsh mud in June to collect samples of = cordgrass. By=20 looking for evidence of fusarium in both the healthy marsh and the parts = that=20 are dying, he hopes to better understand what role the fungus = plays.

This=20 is not a simple task: There are more than 200 species of fusarium. What = Elmer=20 has found here so far is a different species from one tied to the = diebacks in=20 Louisiana. And, he said, a small worm that attacks plant roots may work = in=20 conjunction with the fusarium to kill the plants.

"Most of the = species=20 [of fusarium] are found as epiphtyes - that is, they live on the surface = but=20 don't cause disease," Elmer said. When the plant is stressed, the fungus = turns=20 deadly.

"My hypothesis is there's an initial stressor - probably = rising=20 sea level."

The most intriguing theory behind the fusarium is = that it=20 arrived here after being carried across the Atlantic Ocean on huge dust = storms=20 stirred up by ongoing drought in northern Africa.

Scientists = estimate=20 that hundreds of millions of tons of dust from Africa may reach the = Southeastern=20 U.S., Caribbean and Amazon basin each year. The dust can carry bacteria = and=20 other pathogens - including fusarium - on a five- to seven-day journey = across=20 the ocean. The dust has been tied to respiratory problems in Florida and = the=20 Caribbean, the declining health of coral reefs and red tide = blooms.

The=20 drought itself appears related to a well-known climate fluctuation, the = North=20 Atlantic Oscillation. It is worth considering that one of the predicted=20 consequences of warming temperatures is greater surface evaporation and = more=20 frequent drought.

Elmer is trying to get a sample of some of the = African=20 dust to see if he can isolate fusarium and compare its DNA with the = local=20 strain.

"If I found the same thing in that dust, then I would be = further=20 along in believing that that's how this pathogen got here," he said. = "Even if=20 it's identical genetically, it doesn't prove it. Dust clouds may have = been=20 coming here for thousands of years."

Whatever the marshes' = problems, the=20 rising sea level spells bad news for the saltmarsh sharp-tailed sparrow. = The=20 secretive brown bird only breeds in high marsh grass from Maine to North = Carolina. Twice a month, the areas where it builds nests are flooded by = the=20 "spring" tides - the especially high water at the full and new moons, = when the=20 sun, Earth and moon are in alignment.

Their first nests are often = washed=20 away. They rebuild right away, putting them in synch with the spring = tides.=20 Barring unusually high tides or heavy rains, they have about 24 days to = lay=20 eggs, raise their young and get them out of the nest before the next=20 flood.

Chris Elphick, a conservation biologist at the University = of=20 Connecticut, studies the sparrows in places like Hammonasset, the East = River in=20 Guilford and the Hammock River in Clinton. The sparrow is not endangered = yet,=20 but sooner or later it probably will be, he said.

It's not = obvious what=20 difference it will make if the sparrow dies out. "But we'll be losing = yet=20 another species, or have another species declining, and that's going on = all the=20 time around us," Elphick said. "We pay attention when the last one of = something=20 goes."

Going Dutch

At Hammonasset Beach State Park = and=20 elsewhere around Long Island Sound, efforts are underway to restore = marshes that=20 had been filled or drained years ago. One might ask if there is any = point to=20 this activity now, or even of studying marshes that, if climate = predictions are=20 on target, almost certainly will disappear.

Roman Zajac seems of = two=20 minds on the subject. Back in his UNH lab, he and graduate student Leah = Pabst=20 use their computers to compare elevation maps to their GPS data and an = aerial=20 photo of Banca marsh taken in 2004.

"If sea level rise is the = driver,=20 there's not much we can do besides going Dutch," Zajac joked, referring = to the=20 Netherlands' famous dikes that hold back the sea.

On the other = hand, he=20 said, their work can at least help us understand how the change is = affecting the=20 area's ecology.

"It may help predict what marshes are more = susceptible=20 than others [to dieback]," he said. "It can be a good planning tool for = marsh=20 protection and shoreline protection."

Pabst is writing her = master's=20 thesis this summer on fish populations in the Quinnipiac River marshes, = where=20 there is plenty of evidence of dieback. She has spent many hours = paddling and=20 pushing a canoe up shallow tidal creeks to gather fish samples, slogging = through=20 sticky mud that can suck your boots down like quicksand.

Pabst is = frustrated by what she sees.

"You try to be objective as a = scientist,"=20 she said. "It's very difficult to do that in the climate we have today. = It's=20 becoming an ethical and moral issue."

"Unfortunately people are = going to=20 have to deal with [global warming] on a personal level - and that's when = it's=20 going to be a problem," she said. "Americans like what they want and = when they=20 want it. They don't want to bend over and do anything because they have = it done=20 for them. ...

"People I work with who are my age, we're pissed = off. We=20 don't want to inherit this problem, and have our kids inherit=20 it."

Contact David K. Funkhouser at = dfunkhouser@courant.com.

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Our Marshes Are Dying