The Massachusetts Division of Marine Fisheries has ordered a halt to all harvesting of blue mussels, surf clams, carnivorous snails, and whole sea scallops from Boston to the New Hampshire border because of an outbreak of red tide.
On Cape Ann, the ban was more extensive, including all bivalve shellfish, the division said yesterday.
Red tide is a naturallyoccurring toxic algal bloom noted for its reddish-brown color. Consuming shellfish that have been exposed to red tide can cause paralytic shellfish poisoning in humans, which is potentially fatal.