how do periwinkles reproduce
Making the world better, one answer at a time. Periwinkles reproduce annually with internal fertilization of egg capsules that are then shed directly into the sea. The female periwinkle lay 10,000 to 100,000 eggs. Periwinkles reproduce annually with internal fertilization of egg capsules that are then shed directly into the sea. The female periwinkle lay 10,000 to 100,000 eggs.