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Conservation Moorings

Moorings in eelgrass leave visible scars (doughnut holes) from the movement of the mooring chains. Boating and fishing activities can also destroy eelgrass beds by stirring up the sediments, making the water too turbid for the sunlight to reach the plants. Salem Harbor has lost more than 70% of its historic resources, probably due to the increase in moorings in the harbor.


Eelgrass restoration project in Manchester by the Sea Outer Harbor

Mooring scars

Existing Eelgrass Scars from Traditional Mooring Systems

Four years after installing 7 conservation mooring systems in Area G, Manchester-by-the-Sea has received funds from the MassPort Logan Airport eelgrass mitigation project to replace all the conventional moorings in Areas G and F with 70 conservation moorings by the end 2014, throughout 50 acres of eelgrass.

Conservation Mooring consists of a helical anchor that screws into the substrate, minimizing its footprint within the bed, and a floating rubber cord that secures the vessel to the anchor. This mooring technology is designed to eliminate scour and associated damage to the eelgrass bed and other habitats on the seafloor.

The Association of National Estuary Programs in October 2010 provided the town funds to replace 7 traditional moorings with conservation mooring systems in the eelgrass meadow off the coast of Manchester-by-the-Sea, Massachusetts. The conservation moorings replaced traditional block and chain mooring systems, which can create large circular scars in eelgrass beds due to the large footprint of the block and the scouring action of the chain as it drags along the bottom. The conservation moorings, which were installed at no cost by our local partner, Crocker's Boat Yard, are attached to the seabed by a helical anchor, which replaces the large concrete block that typically serves as the footing. The chain is replaced with a floating elastic cord that eliminates scouring of the eelgrass bed.

Prior to the installation of the new moorings, a team of divers from MA MarineFisheries (DMF) and the U.S. Environmental Protection Agency (EPA) collected baseline information on the size of the mooring scars at each location in order to begin monitoring eelgrass recovery.


In the spring 2011, eelgrass was transplanted into a subset of the scars by a team of divers from DMF and EPA. Monitoring will follow to determine whether transplanting is necessary to facilitate the transition to a healthy eelgrass bed. To learn more about this project, see Use of "Conservation Moorings" as a Component of Eelgrass Restoration in two Massachusetts Harbors (1.6mb PDF)


A special thanks to LighHawk Volunteer Aviators, who will take aerial photos during the course of the project to document the recovery of the eelgrass beds. The Massachusetts Bays Program (MBP), in partnership with the
Division of Marine Fisheries (DMF), was awarded a grant from the Association of National Estuary Programs and the National Oceanic and Atmospheric Administration with additional funding support from The Nature Conservancy.


Conservation Mooring Providers:
Dave Merrill - 603-672-1751 &
Jeff Lefebvre, Hazelett Marine - 802-863-6376

Seaflex, Inc. - 310-548-9100