The last of our top 25 is a little offbeat, but with good reason. Every fisherman should know something about fish themselves-from behavior to ecology to the conservation of native species. Author Peter Moyle is a living oxymoron-an ichthyology professor who writes clearly. Moyle, who teaches at the University of California (Davis), helps all fishermen with his easily read and often entertaining Fish: An Enthusiast's Guide (278 pp., 1993. Illustrated. Published by the University of California Press, Dept. FS, 2120 Berkeley Way, Berkeley, CA 94720. Softcover, $13.95).