Willis E. Pequegnat, 79, biologist, ecologist, author and teacher who taught for 20 years at Pomona College in Claremont, where he was head of the zoology department. He earned his doctorate in zoology in 1942 at UCLA and worked as a ranger naturalist at Yosemite National Park before joining Pomona. During the summer he taught marine biology at Caltech's laboratory in Corona del Mar. In 1960 he was named program director at the National Science Foundation, serving two years, and then taught in the graduate oceanography program at Texas A & M, retiring in 1980. Pequegnat also served as a consultant to governments, oil companies and environmental concerns. In La Jolla on April 2.