Detecting sharks can be driven by the nose

One of the great mysteries of sharks is how they navigate a straight line.

A new study, published in the journal PLOS ONE on January 6, concluded that the sense of smell can help sharks navigate in the ocean , perhaps based on this ability to feel. Chemical changes in water when swimming.

"We have known for a long time that sharks are able to travel long distances. They go far, along fairly straight paths," - Andrew Nosal, a researcher at the San Diego Institute of Oceanography (USA). said. "The question is, how exactly do they do this?"

A leopard shark in the experiment, wearing tracking devices on the fins.(Source: Fox News).

To test, Mr. Nosal and his colleagues arrested 26 leopard sharks living in the coastal areas of La Jolla, California and brought them away from the shore about 9km. They temporarily reduce the olfactory ability of half of sharks by inserting cotton balls into their nostrils. After that, both the fish are attached monitoring equipment and released.

As a result, the non-clogged sharks surpassed 62.6% of the swimmer's distance after four hours, following relatively straight roads. In contrast, the group of snubbed sharks swim only 37.2% of the distance to shore, and swim along more winding roads.

"Some sharks are not covered by the nose, but we are moving away from the sea, first they start swimming away from the shore, but within 30 minutes, they made a U-shaped circle and swam very close to shore, " Mr. Nosal said. "The children who were covered with the nose were not able to get close to the shore like that and their roads were also more sinister."

In fact, in this study, some nose-blocked sharks also returned to shore, suggesting that there may be other signs that may help sharks find their way home. It could be a sound signal such as the low-frequency sound of waves hitting the shore or geomagnetic signals from the school that turtles also use, the researcher said.