Lately there are more and more good books on natural history written by scientists for the general reader. Excellent books by nonscientists are much harder to come by, and Richard C. Davids's ''Lords of the Arctic'' is certainly one of them.
Mr. Davids has an enthusiasm for anything to do with polar bears, and he has devoted an impressive amount of study to the literature, both historical and scientific.
Of course, reading about the great white bear takes one only so far, so Mr. Davids has also logged a good deal of time on the ice. His own experience in tracking, watching, tagging, and weighing polar bears gives the book an immediacy and a pleasant tone of authenticity that no secondhand account can convey. He writes of the fascinating, dangerous unpredictability of polar bear behavior as a man whose life has at times depended on the quality of his observation.
We learn about the white bear's seasonal eating habits, migration patterns, and hunting. We also learn about the folklore surrounding the species. Some of the Eskimo accounts are quite moving. A modern Canadian account is more humorous: ''At the Legion Hall, a bear walked in at midday and proceeded toward a crowd of dart throwers until the Club Steward, an old English Army major, saw him and shouted, 'You're not a member. Get out!' The bear left.''
Mr. Davids also provides a bibliography on arctic wildlife and exploration, which could turn any arctic enthusiast into an armchair expert.
Though Mr. Davids' easy anecdotal style makes research pleasant to swallow, much credit for this admirable book must go to Dan Guravich, whose photographs of bears hunting, eating, looking out of airplane windows, and just enjoying being bears deserve a place among the finest wildlife photography anywhere.
''Lords of the Arctic'' is a book worthy of its subject, and well worth the price.