Bringing back coastal treasures cont'd...

Return of the mummichogs

Last fall, the Town of Essex installed a large culvert at the Conomo Point marsh to replace an undersized one that for decades had impeded salt water flow into the upper marsh, creating a stagnant ditch and clumps of phragmites. By restoring normal tidal flooding, the 1.2 acre (.48 hectare) marsh should eventually become home to sticklebacks and mummichogs that will in turn eat mosquito larvae and become food for sandpipers and other wading birds. And the more salt in the soil and water, the more likely phragmites and other non-native plants will retreat.

Citizens are also helping to ensure restoration measures are succeeding. A key mover of restoration projects, the Massachusetts Audubon Society’s North Shore office, involves school children in the process. Working with scientists the kids learn to monitor the growth of phragmites, study the affect of salinity levels on salt marsh vegetation and assess tidal restrictions and their impact on fish. Since students return to the same sites every year, the data collected reflect the long-term changes within repaired marshes. Elizabeth Duff, the program’s coordinator, says the information helps scientists advise local, state and federal agencies about how to protect and restore salt marshes.

New Franklin School students and volunteers planting wildflowers at North Mill Pond. Photo courtesy of Steven Miller

Eight Towns & the Bay and Salem Sound 2000, two regional groups sponsored by the Massachusetts Bays Program (MBP), launched a program two years ago to train North Shore volunteers to gauge the condition of marshes using biological indicators. The Wetlands Health Assessment Toolbox, or WHAT, is based on an approach developed by Jan Smith, the director of the MBP and Bruce Carlisle of the Massachusetts Office of Coastal Zone Management.

In a series of workshops, volunteers study seven marsh parameters: birds, plants, water chemistry, land use, tidal influence, fish and benthic macroinvertebrates. With Vivian Kooken, WHAT’s volunteer coordinator, as their guide, volunteers then hit the marshes to collect data. For example, at one site on the North Shore where a culvert had col-lapsed, volunteers collected insects to determine how the resulting tidal restriction affected water chemistry.

Their samplings found aquatic beetles called water boatman (corixidae), a freshwater species. Like phragmites, the presence of the insects suggests poor salt marsh habitat. “Bugs are one of the best indicators to use because they are very sensitive,” Kooken says.

At the Conomo Road marsh site, volunteers compiled two years of baseline data before the new culvert was installed. The initial assessment has shown a great improvement in tidal flow. Additional monitoring will continue this summer and Kooken is optimistic. “We’re looking forward to seeing some good changes,” she says.

As volunteers collect specimens, WHAT scientists duplicate those efforts using the same parameters in the same field. The two data sets are then com-pared for quality control. The information gathered paints an overall picture of the marsh’s health. The data are later compiled into a report and distributed to volunteers and government officials.

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