Amakusa is where kuruma prawn farming in Japan began. On Iwajima, in Oyano in Kami-Amakusa, wild prawns were penned and grown on, and that was the start of it. More than a hundred years ago.

The explanation given for the quality is two things together: a sea carrying a lot of minerals, and close management of the ponds. What comes out is thick in the body and sweet, and it snaps when you bite it.

Eaten raw, the sweetness arrives immediately and fills the mouth, and the texture is the other half of it.

Grilled with salt, the flesh tightens up and the sweetness keeps coming out the longer you chew at it. The heads go into miso soup and give it everything they have. Some places fry the shells and serve those too, so that nothing is left. Beyond prawns there are restaurants working with the fish landed at Sakitsu, and sushi counters serving whatever the season happened to bring in that week. The islands here are split into many pieces, and each piece has its own harbor. The prawns raised here are grown from eggs taken from wild Amakusa stock, so the line has not been brought in from elsewhere. It started with somebody deciding to build a fence in the sea and then wait.