Wednesday, January 16, 2013

Oyster Reef Restoration Talk Very Informative

Last night MOP sent a delegation to Dr. Jonathan Grabowski's talk on the Eastern Oyster. It was a very interesting evening due the historic location and the fascinating talk. 

Map of Nahant Peninsula
Nahant Peninsula Off of Lynn, Mass

The  Marine Science Center of Northeastern University is located on a spit of land at the end of the spit of land that is Nahant. The talks was given in a room that was part of a bunker built during World War 2 that housed 16 inch cannons like those that would be used on a battle ship. Around Boston there were a number of siting towers such that if an attacking Navy were to approach Boston Harbor, they could quickly and accurately locate the enemy vessels, target them and send enormous shells to welcome them. Because the Peninsula is far out to sea, the Nahant guns could eliminate the ships before they were in firing range of metropolitan Boston. 

Those guns were never used in battle. However, when they were fired in testing, the report noise broke many windows around the town. A local gentleman attending the event told me of this and that the location is open once a year for a full tour.

Map of World War 2 Gun Emplancement Nahant Mass
Map of East Point Gun Emplacement Nahant

Dr. Grabowski's talk (THE EASTERN OYSTER: AN ICONIC FISHERY AND VALUABLE HABITAT) was terrific in that he shared with the audience a history of the oyster fishery, the environmental value of oyster reef and his experience with oyster reef restoration. Some of his restored reefs in the Carolinas are as much as 14 years old. 

He discussed how theoyster reefs that were once prevalent from NH to Texas rose up to 30 feet from the bottom. These reefs were documented as hazards to ships in a number of areas including the Carolinas and Boston. Those reefs not only supported oysters who grew-up on the shells of their predecessors, but also, they provide shelter to other creatures who hide in the nooks in crannies. Over-time those mountains were reduced to molehills by ever more sophisticated dredging techniques. As a result the coastal habitat became degraded and there is less biodiversity.  

He also gave a timeline for when the native oyster reefs were effectively fished out. The oyster reef infrastructure was eliminated from North to South. After this time commercial growers would import seed oysters, grow them out and then harvest them for market when they reached suitable size.
  • Massachusetts 1820
  • New York 1830
  • Chesapeake 1894
  • Georgia 1908
Globally over 95% of the world's oyster habitat has been eliminated. He pointed out that man is very good at capturing a target that does not move. 

Dr. Grabowski was unaware of any significant specific natural oyster reef in the state. However, he felt there might be some in Wellfleet. He did have an oyster reef restoration project in Ipswich that will be interesting to learn more about. 

He shared with us the longitudinal data on oyster reef he created in North Carolina. His team built the reef by laying down shell and relying on natural spat to settle on it. (This technique has been used recently in Wellfleet.) In the ensuing 14 years it had tripled in area and grown from 6 inches deep to 30 inches deep.   
He then presented some ways that academicians could think about the value of a hectare of oyster reef.
  • favorable impact on fish harvest $4,123 per year.
  • nitrogen removal $7,000 per year
The information aptly illustrated that oyster reef is a valuable habitat and that oyster reef restoration is well worth pursuing. .     

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