The toheroa has long been esteemed as one of our finest sea foods, but unfortunately supplies are limited and strict controls have to be enforced. This clam, which grows to 6 in. in length, burrows deeply in sand on beaches that are backed by extensive sand dunes. Freshwater seepage from lagoons in the dunes promotes the growth of diatoms and affords a rich inshore concentration of plankton, upon which the toheroa feeds. The pattern of distribution is interesting. The largest beds of toheroas are in North Auckland, on the Muriwai Beach, near Dargaville, and on the Ninety Mile Beach, but they also occur on the Wellington west coast beaches near Levin, and on some Southland beaches bordering Foveaux Strait.
by Arthur William Baden Powell, Assistant Director, Auckland Institute and Museum.