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New Hampshire Department of Environmental Services

Three Things You Can Do To Improve The Oyster Beds In Great Bay

If you are an oyster harvester, you are well aware of the decline of this valuable resource. Over the past ten years, a combination of adverse environmental conditions and the outbreak of an oyster disease (MSX) have damaged the oyster stocks such that harvesting your daily limit is a difficult and time consuming task. Now is the time to do something positive as sportsmen to help out the oysters. The New Hampshire Fish & Game Department urges you to do the following three actions: oyster shell recycling, oyster shell return and oyster drill (snail) removal. These are discussed below.

Oyster Shell Donation/Recycling

Several oyster bed restoration projects are currently being implemented in the Great Bay Estuary by researchers at the University of New Hampshire and other organizations. The scope and success of future projects will depend on the availability of clean oyster shell, which is used for remote setting of hatchery-reared oyster larvae but is currently in short supply. After they have consumed their catch, recreational harvesters can help address the current shortage by donating their shell for use on future restoration efforts. The UNH Jackson Estuarine Laboratory has created a program to enable harvesters to conveniently dispose of their shell AND help oyster restoration projects in the Great Bay Estuary. More information on the program can be found at Grizzle Coastal Consulting Oyster Shell Recycling.

Oyster Shell Return

The settling larval stage of oysters (spat) greatly benefits from having a good surface to strike upon. In nature, this is typically existing oyster shell. The removal of oyster shell by oyster harvesters is an unavoidable consequence of oystering. However, the oyster harvester should consider returning shell to the beds, which would increase suitable habitat for settling spat. The timing of shell return would be best in late June before the season closes. The spatfall can occur as early as mid-August and may extend into September. Providing more shell to set on is one simple thing we can do to help increase oyster reproduction.

Oyster Drill Removal

One of the most damaging predators of newly set oyster spat is a snail known as the oyster drill (Urosalpinx cinerea). This snail and its egg cases can be easily identified by oyster harvesters as they cull their catch. Their destruction or removal from the beds will save many spat. A sketch of this snail and its egg case are shown below. Egg cases are typically in clusters.

Oysterdrill graphic Snailcase graphic

Cluster graphic

NH Fish & Game Logo Illustrations from UNH Cooperative Extension Service.

New Hampshire Fish and Game Department, Marine Fisheries Division, 225 Main St., Durham, NH 03824 (603)868-1095


NH Department of Environmental Services | 29 Hazen Drive | PO Box 95 | Concord, NH 03302-0095
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