Researchers from the Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project have uncovered a unique ecosystem of fish and invertebrates living in an estuary deep beneath the Antarctic ice.
The discovery stems from the WISSARD project’s investigation of the grounding zone of Whillans Ice Stream of the West Antarctic Ice Sheet, 850 km from the edge of the Ross Ice Shelf in Ross Sea.
Using the hot-water drill, the scientists punched through 740 meters of the Ross Ice Shelf on January 8, 2015.
“The drill system, described in the Annals of Glaciology, works like an industrial-scale water-treatment plant on skis, which pumps filtered hot water at moderately high pressures of 500 to 800 pounds per square inch through a hose that is equipped with a weighted drill head and nozzle,” said team member Dr Frank Rack from the University of Nebraska-Lincoln.
“It took about three days to drill through the ice, with the hose advancing slowly downward as the nozzle and drill head melted the ice.”
On January 16, the WISSARD team deployed a remotely operated vehicle (ROV) called Deep SCINI to explore about 400 square meters of the marine cavity around the borehole.
The camera-equipped ROV detected a variety of fish and invertebrates in an ecosystem that may provide new insights into how creatures survive and thrive in a brutally cold (about minus 2 degrees Celsius) and dark environment.
“Finding fish, or any other type of life, under an ice shelf is by itself not novel,” said team member Prof John Priscu of Montana State University.
“I have been investigating these types of environments for much of my career, and although I knew it would be difficult, I had been wanting to access this system for years because of its scientific importance,” added team member Dr Ross Powell of Northern Illinois University.
“Findings such as these – gaining an understanding of the ice sheet dynamics and its interaction with ocean and sediment, as well as establishing the structure of its ecosystem – are especially rewarding. It’s a big pay-off in delayed gratification.”
Although life has been found previously under the Ross Ice Shelf, the current site is the closest to the South Pole where such marine life has been documented. The southernmost ocean waters in the world are only 70 km south, under the Ross Ice Shelf at about 85 degrees South latitude.
“This is the first time that Deep-SCINI ROV has been used in the field and it passed this test with flying colors, collecting video of fish living under the ice shelf in this extremely hostile environment far from the front of the ice shelf,” Dr Rack said.