Trace Elements For Fish Production

Press, Volume C, Issue 29673, 17 November 1961, Page 20

Trace Elements For Fish Production

The fish production in some of New Zealand's lakes could probably be increased with the application of trace elements found lacking in the water. This opinion was given in Christchurch by an American assistant professor of zoology engaged on research into trace elements deficiencies in fresh water. He is Dr. C. R. Goldman of the department of zoology at the University of California who spent two days in Christchurch before leaving for the Antarctic. Dr. Goldman said the fresh water trace element theory was similar to that applied in agricultural production in the Dominion. Dr. Goldman has already conducted considerable research into his subject in the United States and Alaska. He spent yesterday at Lake Coleridge doing follow-up work on that done there by his assistant two weeks ago. His work at Lake Coleridge was done in co-operation with Mr M. Burnett, of the Marine Department. By using radio-active car-

bon as a sensitive measure, Dr. Goldman can detect what chemicals are deficient for the growth of algae in a particular lake. Once this has been determined the addition of very minute quantities of the deficient element can increase aquatic plant life which in turn provides more food for the lake's fish life Dr. Goldman in his investigations in the United States discovered a lake in California which was deficient in molybdenum, a trace metal, and also deficient in sulphur and potassium. Normally, the trout in this lake only grew to an average of lOdn. It is Dr. Goldman’s belief that when next year the deficient trace chemicals are introduced the size of the trout could be increased. His trip to the Antarctic is Dr. Goldman's first Once there he will conduct studies on basic energy sources and pathways in ponds and lakes in the McMurdo Sound area. No stranger to polar work, he has already spent three summers in Alaska doing similar research in red salmon lakes.