The reappearance of robust northern shrimp stocks, believed to be the result of strong 2003 and 2004 shrimp year-classes, has industry people hoping they’ll be able to maintain a productive product stream that down the road could translate into increased economic benefits and stability for harvesters and processors. 

Vincent Balzano, captain of the North Star out of Portland, ME has been working with Pingguo He of the University of New Hampshire to develop a new size-sorting grid system for the fishery in addition to the industry standard Nordmore grate. 

New grid design

Commercial shrimp fishermen are required to meet various gear restrictions, including a minimum mesh size of 1-¾” and required use of a Nordmore grate.  They also must abide by a prohibition on mechanical devices used to cull, grade, separate, or shake shrimp on board.

With support from the Northeast Consortium, He and Balzano have designed, manufactured and evaluated a new size-sorting grid system. The operating theory behind the design is to first direct small shrimp to a size-sorting grid where they exit the net, while the targeted large shrimp pass through a standard Nordmore grate and proceed to the cod-end.  Finfish would continue to exit through an escape vent located at the top of the second grid. 

Testing

The designs were tested at sea during the 2005-2006 shrimp season aboard Balzano’s North Star and the Persistence, owned and operated by Tim Eddy of Portland, Maine. The prototype reduced small shrimp landings considerably, by 18-20   count per pound. The next logical step was to begin making this technology available to the shrimp industry and see how it fares under commercial fishing conditions.  Carl Bouchard, captain of the Stormy Weather, used the dual grid system during the 2007 season with great results.  Carl’s counts were consistently lower than the fleet average using the prototype.  If the resource sustains itself and the market demand    continues to increase having a lower count will provide more opportunities for increased revenue.

Fishermen interested in an at-sea demonstration or in using the gear should contact Pingguo He at <phe@ceunh.unh.edu> or Ken La Valley <ken.lavalley@unh.edu>.