Muddy, buggy marsh science: APCC team gathers data for Pine Island Project
Improving tidal flow can be good news for salt marshes. But before any work takes place, it’s vital to fully understand the dynamics of an area, and that’s where science takes the lead.
And that’s why a team from the Association to Preserve Cape Cod (APCC) was out in the vast Pine Island salt marsh on a recent afternoon.
An Association to Preserve Cape Cod (APCC) team heads out into the marsh near Pine Island to install temporary monitors that will measure water levels and salinity. Photo by Gerry Beetham
Harwich Conservation Trust (HCT) purchased the 2.5-acre island from former owner Wayne Coulson in 2025. The nearby Herring River is named for the feisty fish that swim upstream to spawning ponds each spring, which they’ve done for centuries. The fish had been in decline for decades, but are making a slow recovery, and preserving land to protect water quality helps.
“This is a special place,” Coulson said at the time. “I’d like to see it preserved, rather than someone build a big mansion up here.”
About the Pine Island Project
Pine Island is an upland hammock island surrounded by tidal marsh that provides an important refuge for wildlife and plays a particularly important role as a resting, nesting, and feeding area for migrating birds. A variety of shorebirds including great blue heron, snowy egret and great egret inhabit the surrounding salt marsh. Deer and other mammals also use hammock islands as refuges.
As part of the Pine Island Project, HCT is exploring the removal of all or a portion of the causeway that connects the island to Lothrop Avenue, as a way to enhance salt marsh restoration. The causeway inhibits the twice-daily tidal flow, and dense invasive phragmites are taking advantage of the causeway barrier by crowding out and displacing beneficial salt marsh plants.
The APCC marsh monitoring team in the vast marsh near Pine Island. Photo by Gerry Beetham
While the fundraising goal has been reached for the acquisition phase of the Pine Island Project, HCT is still raising funds for the engineering study in support of causeway removal and salt marsh restoration. Please consider a donation to preserve this special place
Eventually, plans call for Pine Island to become a true wildlife refuge, providing habitat for birds and other animals, without the presence of people. There would be no pedestrian access to the island.
Surrounded by salt marsh, the forested island sanctuary could allow wildlife to thrive undisturbed as they forage for food and raise their young.
Into the marsh
“Our purpose here at the Pine Island salt marsh is to assess the salt marsh condition,” said Jordan Mora, APCC’s Lead Ecologist and Science Advisor, as she assembled equipment. “We know that the causeway is impacting tidal flow into this area, because there’s Phragmites australis–an invasive species–growing in the marsh.”
Mora also wanted to gain more information about the impact of berms in the marsh, small embankments that were likely used historically to cut off tidal flow for agricultural or livestock grazing purposes.
Jordan Mora, Lead Ecologist and Science Advisor for the Association to Preserve Cape Cod (APCC). Photo by Gerry Beetham
There is some concern that the berms, along with filled-in ditches, may be causing some waterlogged conditions in the soil, which can stress or kill the roots of salt marsh plants. This could lead to subsidence in the marsh, a gradual sinking of an area. “We really don’t want subsidence these days because of sea level rise,” said Mora.
The APCC team installed monitors in the marsh that will collect water level and salinity data over the next month or so. The setup looks similar to typical PVC tubing, but with the added payload of data-gathering guts. The tubes are installed perpendicularly into the marsh surface, with one end sunk two or three feet into the soil.
‘More efficient tidal flow’
“Mainly, we want to make sure that the plants are happy–if the salt marsh plants are happy, then the salt marsh functions pretty well,” said Mora. “If the salt marsh plants don’t have enough tidal flow–meaning they don’t get enough salinity or pulse from the tide, that means they can get outcompeted by things like phragmites or freshwater species.”
Mora was asked what the benefit of removing all or part of the causeway might be. “We think it would get a more efficient tidal flow into this area of the marsh,” she said, pointing to a large swath of thick, invasive phragmites. “You can think about it as invasive species management, but you could also think about it as restoring some resilience and function to that area of the marsh.”
You might wonder what it’s like to march out into a huge marsh to pound scientific pipes into the ground. It’s certainly no walk in the park. “It’s muddy and it’s buggy,” said Mora. “And there’s always the chance you could get stuck in the mud.”
HCT is grateful for the expert assistance provided by the APCC team and we look forward to their findings. In the meantime, we’ll concentrate on other marshy pleasures, like soaring ospreys, busy fiddler crabs, and the ever-changing parade of tides.
Photo gallery: HCT volunteer photographer Gerry Beetham captured these great images of the APCC team in action at the Pine Island salt marsh:
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