Monday, October 29, 2012

Why Sharks Whale Always to Sea Level?

Why Sharks Whale Always to Sea Level?: Whale sharks can dive in the cold waters to a depth of hundreds of meters. However, the biggest fish Worldwide should always go back to the sea surface.

"They went to the surface to warm up," said Michele Thums of the Marine Institute, University of Western Australia, presented the findings of a team of researchers who studied the behavior of the whale sharks.


He said the findings open up new insights about the behavior of whale sharks (Rhincodon typus), which has not been revealed. Formerly known that whale sharks are regularly diving at a depth of about 100 meters and then back to the surface quickly. This movement is called immersion style "bounce" or "yo-yo".

However, the research team, involving Professor Mark Meekan of the Australian Institute of Marine Research, discovered that whale sharks can also do very deep dives lasting more than two hours.

Whale sharks always come back periodically surface between one dive and the next dive. This pattern is similar to those found in marine mammals, such as whales or dolphins, which are necessary to the surface to breathe.


"But the whale shark is a fish that does not need to breathe air," says Thums. So he and his team went into the field in search of the answer to that phenomenon.

Research conducted on the four whale sharks. Three sharks at Ningaloo Reef off the northwest coast of Western Australia, and one other on Christmas Island. The four sharks characterized by depth and time recording devices that can also record dives in water temperature.

The data obtained from the device revealed that the sharks spend the longest time on the sea surface after a dive the deepest and coldest, the average temperature at 340 meters with around 14 degrees Celsius.

"The whale shark is at the surface averaged over 145 minutes," says Thums. He concluded that behavior arise because the whale sharks takes regulate their body temperature. Whale sharks regularly to the surface to warm up after spending time in the deep ocean where the temperature cool.

Whale sharks, like other types of fish, are ectothermic. Their body temperature to adjust to the temperature of the surrounding water. Whale sharks can not regulate their body temperature through internal physiological processes such as mammals. Eventually they develop behaviors to the sea surface temperature is warmer to warm the body.


"Similar to a regular reptiles bask in the sun to warm the body. Reptile then occasionally move down a rock when his body felt warm enough," says Thums.

He and Professor Meekan published a study titled "Evidence of Thermoregulation by the World'' s Largest Fish," in the journal Journal of the Royal Society this week's issue.

According Meekan, a complete understanding of the behavior will help develop conservation strategies and management of these plankton-eating animals effectively. These findings can also be used to predict the impact of environmental change on whale sharks.


Sources:
tempo.co

Comments :

0 comments to “Why Sharks Whale Always to Sea Level?”


Post a Comment