Tokelau, known previously as the Tokelau Islands, is a dependent territory of New Zealand in the southern Pacific Ocean. It uses the New Zealand Dollar as circulation currency, but has been issuing a variety of non-circulating coins since 1978, and has also authorised some foreign mints to issue bullion coins under its jurisdiction.
The silver ounce (abbreviated as 1 oz) is an internationally popular format, and is denominated as Five Dollars.
This design is the eighth issue in a twelve-year series of bullion coins called Marine Life (or Tokelau Sealife), and features the Porcupine Fish.
Porcupinefish are fish belonging to the family Diodontidae, also commonly called blowfish and, sometimes, balloonfish and globefish. Porcupinefish are medium- to large-sized fish, and are found in shallow temperate and tropical seas worldwide. A few species are found much further out from shore, wherein large schools of thousands of individuals can occur. They are generally slow-moving.
Porcupinefish have the ability to inflate their bodies by swallowing water or air, thereby becoming rounder. This increase in size (almost double vertically) reduces the range of potential predators to those with much bigger mouths. A second defence mechanism is provided by the sharp spines, which radiate outwards when the fish is inflated. | 
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