The gurnard's giant pectoral fins look dangerous ... and that's the point! When threatened, these incredible fish fan them out to scare off predators. The fins also come in handy for "walking" along the ocean floor or poking around in the sand for food. The name "gurnard" comes from the French word for "grunt", which is apt as the fish are known to emit growling sounds through their swim bladder. However, flying gurnards don't actually fly – although some sources claim they can glide above the surface for brief stints using their large pectorals.