Shellfish Harvesters and College Students Working Together in the Kennebec Estuary

Category: Uncategorized

By:  Gabi Serrato Marks

In this series, TEX is featuring a number of blogs from student volunteers who assisted at AGU’s Fall Meeting in December 2015. Each volunteer was asked to find community science projects in either oral or poster sessions and describe how the project aligns with the TEX mission and values. 

Bowdoin students (right) at a Kennebec Estuary clam flat with Ruth Indrick (left), KELT Project Coordinator, to take samples. Image: Michèle LaVigne.

Bowdoin students (right) at a Kennebec Estuary clam flat with Ruth Indrick (left), KELT Project Coordinator, to take samples. Image: Michèle LaVigne.

Generations of shellfish harvesters in New England have accumulated knowledge about clamming, including the idea that adding crushed clam shells back to the flats can help to strengthen weak clams. When more and more clams began to break and show signs of weakness, clam diggers along the Kennebec Estuary in mid-coast Maine wanted to find out if acidic conditions in the flats were causing the weak shells, and if adding crushed shells would help to counteract it. Shellfish harvesting is still one of Maine’s major industries (the softshell clam harvest alone brought in almost $17 million in 2013), but decreased harvests hurt small, coastal communities like those along the Kennebec. Shellfish harvesters turned to local shellfish committees and the Kennebec Estuary Land Trust (KELT) for help with the weakened shells.

Bowdoin students digging for clams (left) and taking water samples (right) at another site on the Kennebec Estuary in Maine. Images: Ruth Indrick, KELT.

Bowdoin students digging for clams (left) and taking water samples (right) at another site on the Kennebec Estuary in Maine. Images: Ruth Indrick, KELT.

KELT began working with local clammers in 2012 when clam flats were being closed frequently due to high pollutant levels. They established a volunteer water sampling program and have obtained more than 500 water samples from 19 different sites, with data on temperature, salinity, dissolved oxygen, and pH (acidity). KELT and clammers wanted to expand their data collection to focus on the effects of acidification on clam flats, so they partnered with Dr. Michèle LaVigne and students in her Marine Biogeochemistry classes at Bowdoin College. Ruth Indrick, KELT’s Project Coordinator, and Dr. LaVigne worked with local shellfish experts to identify flats where further data would be most beneficial to the community, including both flats with weak clams and those with strong clams. The sites span a gradient from fresh to salty throughout the Kennebec Estuary.  Bowdoin students are now testing sediment, clams, and water characteristics at flats along the estuary to find the problems contributing to weak shells. The research is ongoing, but Ruth, Michèle, and a group of students recently presented the current data to interested residents at a well-attended evening lecture. Clam diggers and KELT will work together to decide how to proceed with the crushed shells technique for flat restoration.  The continued partnerships between local clam diggers and scientists have the potential to make a real difference in mid-coast Maine in the years to come.

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