by Washington (AP) – Some dolphins in Australia have a special technique to rinse fish from the sea floor. They hunt with a sponge on their beak like a clown nose.
With the sponge to protect against sharp rocks, the dolphins swim with covered barrels, shovel through rubble on the bottom of the sandy channels and stir in the sealed sand packaging for a meal.
But this behavior – passed on for generations – is more difficult than it looks like it looks like it looks like it looks.
The hunt with a sponge on the face affects the finely coordinated feeling of echolocation of the Engpinse Dolphine, emitting noises and listening to Echos to navigate.
“It has a villain effect in the way a mask could,” said co-author Ellen Rose Jacobs, marine biologist at the University of Aarhus in Denmark. “Everything looks a bit strange, but they can still learn how to compensate.”
Jacobs used an underwater microphone to confirm that the “sponge” dolphins in Shark Bay, Australia, still used Echolocation clicks to guide them. Then it modeled the extent of the sound wave distortion from the sponges.
For the wild dolphins who have mastered the food search with nasal sponges, scientists say that this is a very efficient way to catch fish. The wild naval sponges vary from the size of a soft ball to a cantalae.
The sponge hunt is “like hunting when you are connected to your eyes, you have to be very good and very well trained to pull it off,” said Mauricio Cantor, a marine biologist at Oregon State University, who was not involved in the study.
This difficulty could explain why it is rare – only about 5% of the Delphin population that the researchers examined in Shark Bay. That is a total of 30 dolphins, said Jacobs.
“It takes many years to learn these special hunting skills – not everyone sticks to it,” said marine ecologist Boris Worm at Dalhousie University in Canada, who was not involved in the study.
Delphinälber usually spend three or four years with their mothers, observe and learn important life skills.
The delicate art of sponge hunting is “only passed on by mother to descendants,” said Janet Mann, co-author and Georgetown Marine-Biologyin.
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