In looking back through the years during which mammal studies have been carried on at Mount Rainier, three periods stand out in which considerable field research was accomplished. The first of these was in July and August, 1897, when a party headed by Dr. C. Hart Merriam, Vernon Bailey, Dr. A. K. Fisher and Walter K. Fisher made the first field studies of the mammals of the park. Following this very important piece of work there was a lull in field activities until the summer of 1919 when a party working under the auspices of the National Park Service and the Bureau of Biological Survey conducted studies on the local bird and mammal populations. In this party were such well known scientists as Dr. Walter P. Taylor, in charge, George G. Cantwell, Stanley G. Jewett, Professor J. B. Flett, Professor William T. Shaw, Professor J. W. Hungate and Mr. and Mrs. William L. Finley. Upon the completion of this study there was again a long period in which little of a systematic nature was accomplished. The last period of note came during the years 1934-1936 when Mr. E. A. Kitchin, a member of the Wildlife Division of the National Park Service, supervised field studies in various portions of the park. Many of these studies were concerned with observational data rather than extensive collecting. For the next few years only brief observations from members of the park staff were added to the park records. Then, during the summer of 1947, special studies were begun by the Naturalist Staff on the status of the mountain goat and the problems arising from a foot disease that occurred in the deer population. It is planned that other special studies shall be carried on in future years, designed to clarify the status of other important mammalian species in the park.

Because of the extensive data that have slowly accumulated through the years since the 1919 survey, the need for a publication to bring all information up to date has become increasingly apparent. This booklet is designed to answer that need.

The sequence of species used brings many of the larger animals ahead of the smaller and more obscure kinds, and thus does not in many cases follow in systematic order. However, it is felt that the order used best meets the needs in a publication of this type. Common names selected are those most generally accepted for the animals in question.