Vineyarders are rightfully proud of the yearly abundance of oysters and scallops pulled from Island ponds, but little is made of what goes back into the water. Jessica Kanozak, creator of the Island’s nascent shell recovery program, hopes to change all that. After the first year of a pilot program on the Vineyard to return seashells to the sea, experts and community leaders met Saturday to discuss the program’s strengths, weaknesses and potential for expansion.