A QUIET POWER marks Margaret Rau's writings for young people. In The Snow Monkey at Home, this author of earlier books on the musk ox, giant panda and gray kangaroo takes complex information from her observation and research and gives it the texture and flow of a compelling story. Snow monkeys are the chattering, lip-smacking fluffy macaques living only in Japan, in heavily forested fastnesses, farther north than any other species of monkeys. The story follows the life of one male, born in the first pages, as he travels with his nomadic troop -- on foraging treks, swinging from branch to branch or, across open spaces, marching in single file, sleeping by night high in cryptomeria trees.

Through the years, experiencing the clamorous mating seasons and winter's bitter weather, this creature moves from the protected center of his troop to its periphery, takes on sentry duty, leads a slinter unit, and in the end becomes a solitary wandering alone. Full-page drawings complement the text of this well-crafted book in which even the bibliography, highly specialized, has class.

How Animals Live Together is a welcome newly revised edition of Milicent E. Selsam's 1963 book on the sociable world of animals, where insects live in colonies and wolves in packs. Author of many science books for children, Selsam received in 1978 an award from the Children's Book Guild of Washington honoring the total body of her work. A botanist and former high school biology teacher, she writes simply and with authority, offering glimpses into research and field work

Photographs here replace the line drawings of the earlier edition. A comparision of indexes shows that dolphin, whale, wolf and mountain gorilla materials have been added, along with a summary of Jane Goodall's work with champanzees and an expanded bibliography.

Bear cubs, batlings, bobcat kittens appear in Wild Babies: a Canyon Sketchbook. Sitting quietly in an Oregon canyon, author-illustrator Irene Brady saw many of the creatures of her book -- even her red-tailed hawks, mating in a bright spring sky -- but she sketched her subjects at animal care centers where tiny orphans are reared and prepared for a return to the wild. Large drawings, one and more to a page, many in tawny shades, give precise detailing of claws, paws, feathers, the stages of antler growth. The choice for the jacket portrait of a bobcat licking a kit, greeting-card trite, seems a disservice to this careful depicter of wild-life.

From observation Francine Jacobs skillfully describes Africa's Flamingo Lake, Nakuru, in Kenya, which attracts hugh flocks, the largest anywhere, of flamingos -- how the lake sits like a bowl of green soup evaporating in the hot sun, how it surface shimmers with the thousands of great pink-and-white birds, how the algae floating in it nourish the birds, tinting their feathers and replace themselves -- 150 tons worth -- in a day. A good final chapter discusses the fragile habitat and how manipulation affects its populations. But some vital design process has been skimped. One third of the book is unrelated to lake or birds. The photographs are dull gray, lacking contrast or sparkle.

The Animal Olympics, with lively cartoon-type color drawings, is a slapdash, conversational what-if? book, imagining animals pitted against human beings in the Olympic games. Its appeal is in its lists and statistics; Howard E. Smith Jr. is no story teller. Snow leopard wins at broad jump; elephant, at shot-put. Dolphin, chamois and puma take gold, silver, bronze medals in the high jump where man and jackrabbit, both losers, are about evenly matched.