Therefore, do not pack them directly on ice because the melted ice can become a problem. A lobster in fresh water swell ups and can burst. Dry ice should not be used either because it produces large amounts of carbon dioxide that can asphyxiate the lobsters. Shipping in seawater is not recommended unless the holding tank is outfitted with aeration equipment. Without adding aeration, a lobster in a container of seawater quickly uses up the dissolved oxygen in the water and suffocates.
Refrigerated trucks are ideal because they maintain the proper temperature and moisture.
For best results, lobsters should be relatively cool before they are packed so that they are not stressed by going from warm to cold temperatures. Although lobsters are more successful at coping with temperature changes in the warm to cold direction, they aren't generally good at coping with rapid changes in temperature. It is also best not to feed lobsters for two or three days before shipping. Full stomachs result in lobsters using more oxygen and increase the incidence of vomiting. No need for messy lobsters.