Tuatua and Southern Tuatua (which is slightly bigger in size) are closely related to the pipi (found mostly in harbours) and the Toheroa (found on west coast beaches from Auckland northwards. Tuatua looks almost identical to pipi which is smaller. Tuatua can be found at low tide on sandy beaches between half tide out to 20m water depth.
Research has discovered that there are two distinct species of tuatua – P. subtriangulata – (has a white shell) is found around the North Island, and the north of the South Island, while the Southern tuatua – P. donacina – (has a grey shell) can be found all around the South Island and also overlaps the tuatua in most of the North Island.
On occasions after a patch of rough weather tuatua are washed loose and can be gathered from the beach with ease. I remember one time at Amberley Beach, near Christchurch, when, after a storm, the beach was littered with them still in their shells. Tautua seems to be able to move up and down the beach and may not be in the same place they were in last week. Tautau can be frozen for use on another day. They can also be kept alive for days if covered with sea water or even a wet sack and kept cool.
Tuatua were, and still are, a favoured food of the Maori. In pre-European times the Maori ate vast quantities of pipi and tuatua evidence of which can be found in numerous ancient midden heaps.
A mate of mine would often take along any old tuatua he had in his freezer when we went surfcasting together. Some he would reserve for bait. With the others he would crack their shells and throw them out into the sea in the area we would be fishing to act as a type of berley. It is hard to say how effective this tactic was but we sure caught plenty of fish!
There are three ways of making tuatua stay on your hooks during casting. The first is to salt them as described below. To my mind, this is not the best as they look like dried prunes and they surely can’t taste too good. Spiny dogfish seemed to like them well enough.
Secondly, you can make cocktail baits. This is a method I frequently use. Thread the end of a length of squid strip on to your hook. Then thread on the flesh of a tuatua or pipi. Then finally the remainder of the squid strip. This way the soft shellfish flesh is sandwiched between the folds of squid. It stays on quite well.
Thirdly, soft shellfish can be tied on with a length of bait elastic about a foot long which is sold specifically for this purpose. Thread the tuatua on to your hook passing the point through as many times as possible. Taking care to avoid any loose dangling bits from hanging down. Then hold one end of the bait elastic against the bait and under tension wrap it round and round the bait until you have used all of it. Take care to avoid the barb becoming clogged with bait. It must be allowed to stand completely free for a positive hookup. Bait elastic is great stuff and well worth the effort. You can also use it to good effect when baiting up with cut baits that have become a bit soft.
Tuatua is an excellent bait for some species more than others. Elephant fish and moki will readily take them as bait.
Shelling tuatua and covering them with rock salt produces surprisingly firm bait. You don’t have to freeze them. Tuatua treated in this way will keep for years in a jar or plastic ice cream container. However, like paua, it wouldn’t be my first choice. Its main advantage is that it can be enough to get you started if you have nothing else available.