Video: This Fish Climbs Up Waterfalls By Gripping With Its Mouth
How to scale a slippery 300-ft rock wall in the middle of a waterfall One genus of goby fish has developed a radical adaptation to life in Hawaii's rough-and-tumble streams: it uses its mouth to climb waterfalls. Waterfall climbing is a critical skill for Hawaiian gobioids--the fish hatch in freshwater streams, but are quickly swept to sea in the fast-flowing currents, and spend most of their adult lives working their way back upstream. Most goby species accomplish this climbing by using a suction-cup-like sucker on their bellies to attach to the waterfall's rock substrate, then rapidly undulating their bodies to propel themselves upward before quickly reattaching again. But goby fish belonging to the Sicyopterus genus have a more economical method of vertical movement--their mouths act as a secondary suction cup, allowing the fish to inch upward without detaching completely from the slippery, steep rock wall: The energy-efficient technique allows the fish...