The largest school of sea animals ever found was being tracked off the Antarctica last week. It took up several square miles of sea, to a maximum depth of 600 feet below the cold surface.

The enormous school was made up of a shrimp-like animal called Krill, and the single school was equal to about one-seventh of the world's total fish and shellfish catch for a year. The school found last week would be enough to supply every man, woman and child in the nation with 98 pounds of crustacean.

"We have never, anytime, anywhere seen anything remotely like this size for one school of animals," said Francis Williamson, chief polar scientist for the National Science Foundation.

"People had been talking about taking as much as 10 million metric tons a year, as a total world catch, in the future," Williamson said. "This one school of animals is 10 million tons."

He said the find makes credible the notion that krill could be a major percentage of the world's fishing in the future.

Krill, a protein-rich animal that grows to a maximum length of about two inches, has begun to be fished by half a dozen nations in pilot projects.

It has been suggested that the animal be mashed and used for such products as animal meal, a new variety of hot dog, a paste for cracker spread or potato chip dip, or simply added to many foods as a cheap way to increase their protein and bulk.

The swarm of krill was spotted near Elephant Island in the Antarctic by the research ship Melville.

Hampered by high winds, fog, and icebergs, the ship got the aid of two West German ships and a Polish one to measure the school with sonar and netting techniques.

Some 35 Soviet fishing trawlers gathered at the site of the massive school as the measurements continued.