Bruce Smith, (603) 868-1095
John Nelson, (603) 868-1095
Jane Vachon, (603) 271-3211
November 20, 2006
Great Bay Oyster Research Offers Hope for Future Stocks
DURHAM, N.H. -- Good news has been in short supply for Great Bay oysters lately, but recent findings from the New Hampshire Fish and Game Department's 2006 oyster reproduction monitoring effort, now underway, offers hope that oysters are on the rebound.
"After gathering and analyzing data from three of the major beds, it is apparent that this year has been an extraordinarily productive and successful spawning year for Great Bay oysters," said Bruce Smith, a marine biologist with Fish and Game's Marine Fisheries Division.
The oysters in New Hampshire's Great Bay have been a valued resource throughout the history of man's inhabitance of the area. First taken by early Native Americans, and later by European settlers, today oysters provide a recreational fishery for hundreds of New Hampshire license holders. New Hampshire Fish and Game Department's Marine Fisheries Division is entrusted with the management of this valuable shellfish.
Over the past fifteen years, annual surveys have measured the abundance of oysters on the major Great Bay beds. One important indicator of the health of the resource is the annual recruitment of young oysters into the population (termed "spatfall"). Spatfall provides a clear picture of the reproductive success for a particular year, and these young oysters, or "spat," may become available for harvesters in about four years.
The success of spatfall over the fifteen-year period of study has clearly shown a lack of a steady and reliable supply of young oysters each year. It appears that the oyster population varies widely in its ability to successfully complete its reproductive function; some years show little to no spatfall, and other years have relatively large numbers of spat. This unreliable recruitment of young oysters into the population was also shown several decades ago, when a multi-year study investigated the possibility of establishing a spat-producing aquaculture operation in Great Bay.
In the 2006 monitoring, total spatfall -- measured from collection by divers of all the shell material in a fixed sample frame (1/4 meter square) -- is in the range of 200 per frame, according to Smith. Previous high numbers have rarely exceeded a tenth of that and frequently have been in single figures.
This year's results give the New Hampshire Fish and Game Department's marine resource managers some optimism that the valuable recreational oyster fishery may see some substantial recovery over the next few years. New Hampshire's oysters face other challenges, such as infection by MSX and Dermo, diseases that weaken oysters and either kill them outright or make them more susceptible to other hazards. These diseases have devastated the oyster beds in New Hampshire, as well as in the Chesapeake Bay and other mid-Atlantic estuaries in recent years.
- ### -