Fullertons Marsh fully tidal for first time in 70 years

The tide flows in and out at Fullertons Marsh again, for the first time in 70 years.

The marsh is at the south end of Fullertons Creek, near Stratford, P.E.I., connected at the north end to the Hillsborough River. 

Ducks Unlimited Canada helped to create the freshwater marsh in 1950, taking advantage of a former railway line across the waterway that acted as a natural dike.

Ducks Unlimited said rising sea levels, creating higher tides, were eroding the dike faster than they could fix it.

So the decision was made to return the marsh to its natural saltwater state. 

"Removing our structure allowed for tidal exchange into the freshwater impoundment, and over time, it will evolve into a functional salt marsh again," said Jonathan Platts, a Ducks Unlimited Canada conservation program specialist for P.E.I.

"It did its job, but we found that in recent years, it was becoming more and more difficult to manage due to sea levels and tidal intrusion into the marsh. It just came to a time where it was time to remove it." 

Important ecosystems

Platts said tidal marshes are important ecosystems, in many ways.

"They provide lots of ecological goods and services to humans, such as flood protection, mitigation against coastal erosion, their contributions to the marine food chain, and also carbon sequestration," Platts said. 

"So if we have an opportunity to remove a barrier, and allow tide to come in and revert that back to what it used to be, I think that's something that we should consider."

Platts said it took about a week and a half to remove the old structure that had been holding back the saltwater for decades.

"It was more challenging than what we thought, it was steel pilings that were driven down into the mud, you know, eight, 10 feet," Platts said. 

"They look to be fairly rusty on top but once we got down underneath, the suction in the mud, it was difficult to pull out. They were all rusted together, but we managed to get it out."

Saltwater returns

Platts said it was exciting to see the saltwater moving into the area that had been freshwater for decades. 

"It was interesting. We could see a lot of the sediment moving back and forth between the two cells. Some of the little fish, like mummichogs and sticklebacks, they were getting into the impoundment for the first time," Platts said.

"Lots of shorebirds coming into the mud flats to feed for the first few days, lots of yellowlegs, spotted sandpipers and gulls." 

Platts said there are some species that would have used the freshwater marsh, that will no longer be present.

"I think some species will be displaced like beaver, they won't thrive in saltwater. You'll still have muskrats," Platts said. 

"But we have lots of breeding habitat in the area now for waterfowl so we're not worried about losing that by converting it to salt marsh."

'Rare resource'

Rosemary Curley, the president of Nature P.E.I., has been following the project at Fullertons Marsh.

"It's hard to argue against a return to its natural state," Curley said.

"The amount of salt marsh on P.E.I., it's limited, it's a rare resource. It's less than one per cent of the Island."

Curley said adding a saltwater marsh is important on P.E.I., where they are being threatened by rising sea levels.

"Returning this to a tidal marsh will compensate for some of the losses that are occurring, and will occur more frequently in the future with sea level rise," Curley said.

"Because as the sea level is rising, marshes have to migrate further inland, and there's quite a few places on the Island where they can't do it, and so this will help compensate for those losses."

Gradual transition

Curley said Fullertons Marsh will slowly transition back to a natural saltwater marsh.

"I think it will be fairly slow. Right now, you can see on the marsh, the yellow area, that's getting tidal flooding now," Curley said.

"Then this area with the tan vegetation, the cattails, is where the fresh marsh was.

"I just recall when the Graham Rogers Lake at North River was opened up and became tidal, it took quite a few years to really see the cattails disappear and the salt-marsh cordgrasses re-invade," Curley said.

"So I don't think it'll be overnight."

Platts said he predicts within five to seven years the renewed marsh will be fully returned to its natural state.

He said Ducks Unlimited is looking at a similar project at Johnstons River, and has started talking to local landowners in the area.

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