Some dolphins in Australia They have developed a special technique to get fish from the seabed. They hunt with a sea sponge on the tip of the snout, like a clown nose.
Using the sponge to protect themselves from sharp rocks, dolphins swim with the tip of the snout and remove the bottom of the sandy channels to detect the presence of some fish to feed.
But this behavior – transmitted through generations – is more complicated than it seemsaccording to new research published on Tuesday in Royal Society Open Science.
Hunt while carrying a sponge on the face interferes with the sharp sense of ecolocation of the bottle nose dolphinswhich consists of emitting sounds and clicks and listening to your echo to navigate.
“It has a silencer effect in the same way that a mask would do,” said Ellen Rose Jacobs, co -author of the Marine Study and Biologist at the University of Aarhus in Denmark. “Everything looks a bit weird, but you can still learn to compensate.”
Jacobs used an underwater microphone to confirm that Shark Bay’s dolphins, Australia, continued to use the ecolocation clicks to guide themselves. Then he modeled the range of the distortion of the sound waves caused by the sponges.
For those wild dolphins that have dominated the search for food with sponges, scientists say it is a very efficient way to catch fish.
Hunting with sponges “It’s like hunting with bandaged eyes – you have to be very good, be very well trained to do it well”said Mauricio Cantor, Marine Biologist at the State University of Oregon, who did not participate in the study.
This difficulty can explain why it is something so unusual, and just around 5% of the population of dolphins studied in Shark Bay researchers carry out this practice. That is approximately 30 dolphins in total, Jacobs said.
“It has been learning this special hunting ability for many years; not everyone continues to use it,” said Boris Worm, a marine ecologist at Dalhousie University in Canada, who did not participate in the study.
Dolphin’s young usually spends about three or four years with their mothers, observing and learning vital skills.
The delicate art of hunting with sponges “is only transmitted from mother to breeding,” said Janet Mann, co -author and marine biologist of Georgetown.