BEIJING, Aug. 7 (Xinhuanet) -- An international team of scientists late last summer glued satellite-transmitting devices to 85 southern elephant seals -- the world's largest -- to help them find clues to growing changes in the global climate in the freezing waters surrounding Antarctica.

The devices monitored water temperature, saltiness and depth, transmitting these data to satellites every time the carnivores briefly surfaced for air for three to four minutes.

The lives of these giant marine predators (males weigh up to 11,000 pounds and reach up to 22 feet long) and their prey has always been difficult to study because they often dive to great depths under the ice in unreacheable regions of the Southern Ocean surrounding Antarctica.

"The fact that we can let the animals themselves measure the oceanography is extremely exciting, being arguably the best oceanographers, since their survival depends on it," said Martin Biuw, a marine biologist at the University of St. Andrews in Scotland.

The southern elephant seals "ranged across the entire Southern Ocean," swimming thousands of miles a year, Biuw explained. Tracking where these predators went shed light on the location of the most productive waters loaded with prey. The salt and temperature readings the sensors recorded suggest these waters were loaded with nutrients from the water currents that encircle Antarctica and from under the winter ice pack.

The study will not only help scientists learn more about these creatures but also how the environment they dwell in alters over time due to changes in global climate, he added.

Future updates with the sensors should allow them to record chlorophyll levels underneath the ocean surface as well, to see how productive photosynthetic life is around the Antarctic.

The findings are described online Aug. 6 in the Proceedings of the National Academy of Sciences.

(Agencies)