The Pacific leaping blenny, a fish that has no legs but remains on land for its entire adult life, baffles scientists as they study the land animal’s unique way of life.
Known as one of the smaller tropical fish, the Pacific leaping blenny is found in reefs along islands in the Pacific Ocean. Remaining on land throughout its entire adult life, the unique fish must fight to stay moist so it is able to breathe through its skin and gills.
The leaping blenny uses its tail-twisting abilities to jump and climb over complex rock surfaces. Baffled by their ability to survive out of water, scientists conducted an exclusive study of the fish to find out more about their way of life.
Senior author of the study Dr. Terry Ord told reporters,
“This terrestrial fish spends all of its adult life living on the rocks in the splash zone, hopping around defending its territory, feeding and courting mates. They offer a unique opportunity to discover in a living animal how the transition from water to the land has taken place.”
According to Ord and co-author Courtney Morgans, after measuring 5 different populations of the Pacific leaping fish, they found that the ocean-to-land animals specifically target rocks of their own skin color to camouflage themselves against predators. Ord goes on to explain:
“They were virtually identical in each case. The fish’s body color is camouflaged to match the rocks, presumably so they aren’t obvious to predators…We put lots of these model blennies on the rocks where the fish live, as well as on an adjacent beach where their body color against the sand made them much more conspicuous to predators.
After several days we collected the models and recorded how often birds, lizards and crabs had attacked them from the marks in the plasticine. We found the models on the sand were attacked far more frequently than those on the rocks. This means the fish are uniquely camouflaged to their rocky environments and this helps them avoid being eaten by land predators.”
More can be read about the study and the Pacific leaping blennies in the paper published by Animal Behavior.
Pacific Leaping Blenny Study Finds New Information on Land-Dwelling Fish.