Research Ship Returns With Data About Krill

After a four-month voyage to the waters around Antarctica, the San Diego research ship the Surveyor returns to its home port today with what local scientists believe is a wealth of new data about krill, and how their diminishing numbers may affect the international food chain.

Rennie Holt is chief scientist with the U. S. Antarctic Marine Living Resources program, based at the Southwest Fisheries Center in La Jolla. Holt, one of 20 scientists and more than 80 crew members on board the Surveyor during its most recent foray into the icy Weddell Sea, said Monday that its focus this time was probing the effects that krill fishing has on other forms of marine life in the region.

Krill are shrimp-like crustaceans and “the food for most of the animals down there,” Holt said.

“Because Antarctica is so cold and dark, almost all the marine life feeds on krill. It’s like a one-step food chain. But several nations are now utilizing krill for food: Japan, the Soviet Union, Poland, East Germany and Korea.

“Krill is a delicacy, high in protein,” he said. “It’s a gourmet food, but it’s also fed to livestock. At the moment, no one thinks these countries are harvesting enough (krill) to have an adverse effect. But some of these nations say they intend to expand their fisheries and their harvesting of krill. We’re trying to provide data to indicate whether or not that’s a good idea or a very bad one.”

The beauty of the research, Holt said, is that each of the aforementioned countries publicly supports the project. Like the United States, all are member nations in the Convention for the Conservation of Antarctic Marine Living Resources, he said.

“Member nations have agreed not to over-harvest,” Holt said. “If someone removes too large a supply of krill, other animals--the whales, seals, penguins and others in the area--will simply not have the food to survive. So our research is important in giving these people something to go on.”

To collect data, Holt said, the scientists affixed transmitter tags to five crabeater seals in the Weddell Sea, one of the many animals that feed on krill. An Argos satellite will track the seals throughout Antarctica’s bitter winter.

“These are the seals associated with the coldest conditions in the winter,” Holt said. “No one knows exactly where they go, so we don’t know where their food goes in the winter, either. We put the tags on them just to get an idea of where they and their food go in winter.”

The research was prompted largely by technological advances that have it made easier and more economical for the Soviet Union and Japan, in particular, to harvest krill, Holt said. The AMLR scientists also tagged and tracked foraging penguins and charted microscopic algae upon which krill feed. Some of the research was also devoted to oceanic conditions in Antarctica.

The Surveyor usually makes two 30-day trips each year, Holt said. He and his group fly to Chile, then cruise to the South Pole. The trip takes four months--a month to get down there and a month to get back, with research sandwiched in between. Holt said the crew of 100 includes scientists and others who work with the project on a contract basis, most coming from academia.

It is an undertaking fraught with peril.

“The weather down there is so variable and so harsh,” he said. “The weather can change in the Antarctic region in half an hour. You can wake up with bright sunshine, and 30 minutes later be completely fogged in. Then you can have sleet and rain and finally snow. If a certain operation requires good weather, you can’t wake up and say, ‘Great, the weather’s terrific, let’s do this.’ You have to say, ‘The weather’s good. Let’s try to do this right now.’ ”

A small crew going to a nearby island will always take compasses even if the mother ship is clearly within view, Holt said. They’re a necessity because of fog. Workers always have radios and tents and enough food for two weeks.