Who knows these Antarctic waters best? Seals, of course. That’s why they will become allies of the scientists studying the region. Seals with sensors will study Antarctica. Who said the dog was man’s best friend? The journal Limnology and Oceanography discusses the study.
Sensor heads
It’s something that’s been done for a few years now. They implement oceanographic data recording equipment on marine animals. In particular equipment that records conductivity, temperature and depth (CTD). CTD data allow scientists to estimate the origin of the water.
“Southern elephant seals and resident Weddell seals, a deep-diving predator, were used. They brought back interesting information from Antarctic areas,” Nobuo Kokubun said. He is an assistant professor at Japan’s National Institute of Polar Research. “But almost nothing from the coastal areas covered by land ice.”
So the researchers conducted a field study with another lens. They attached sensors via CTD satellite to the heads of eight Weddell seals. It was conducted from March to September 2017.
The sensors weighed about half a kilogram. They were about the size of a small Rubik’s cube. What did the data transmitted from the instrumented seals say? It turned out that warm, low-salinity water appeared in the subsurface during the fall. It got deeper as the season progressed.
Natural Investigators
It is caused by the easterly wind that prevails during the autumn. It causes a flow of warm surface waters off the shelf. And possibly additional prey onto the continental shelf. This had positive effects on the foraging behavior of the seals.
Seals with sensors will study Antarctica for a while longer yet. It has proven to be a powerful tool. They will explore a wide range of Antarctic continental shelves covered with land ice. It will help predict how the Antarctic coastal marine ecosystem is responding to the rapid changes underway in Antarctic sea ice.
