Manta Trawl Tested Aboard Inland Seas

During last week's Young Women in Science cruise, ISEA tested a Manta net, used to collect surface organisms and to look for micro-plastics (break-down products of plastic materials).  The Manta net consists of an aluminum frame with welded aluminum "wings" on each side to keep the net on the surface, and a long net with 353 micron mesh size.

Manta Trawl being deployed from Inland Seas

The net is pulled behind the schooner for 30 minutes at 2 knots.  We did two trial runs, one in Suttons Bay and one in the West Arm of Grand Traverse Bay. The Suttons Bay sample consisted of a large amount of midge pupa cases, terrestrial insects, leaf matter and pollen.  The West Arm sample had few terrestrial items, but did contain a lot of material that will need to be sifted through to see if there is any micro-plastic bits present.  The samples were preserved in alcohol and will be given to Dr. Sherri Mason of the State University of New York - Fredonia for analysis.

Manta recovery after 30 minute tow. 

We plan to take Manta net samples throughout June and July for Dr. Mason.  This is part of a larger effort to  describe the implications of micro-plastics on a world-wide basis.

Click here to see Dr. Mason's PowerPoint on plastic reduction ideas.

Click here to see the impact of plastic on Midway Island albatrosses.

Capt. T. Kelly