These white shells have an incredible history. They are barnacles (Coronula Diadema) that live only on a whale species. These are the white spots that are often seen on the head of whales when they come to breathe on the surface. The animal that lives in this shell spreads feather-shape tentacles, to feed on plankton. This species lives on humpback whales, whales that reach 14 meters in length and 25 tonnes. But when a whale dies, it will eventually sink, and those shells have been hauled back into fishing nets. These shells once swam on a whale!