AbstractsBiology & Animal Science

Prior to the present work, no detailed study had been made of the amphibians and reptiles inhabiting Benton County, Oregon. Very little has been published on the precise ranges, the habitat preferences, and the mode of life history of these animals as they are found in Benton County and adjacent areas. This lack of knowledge has existed as a considerable handicap to students desiring to do work with these forms, in that they have had little knowledge of where each species or subspecies occurs, or their habits throughout the year. The present paper was undertaken with the objectives in mind of studying the natural history of the local amphibians and reptiles as completely as possible, although the subjects of distribution within the area and of habitat preferences have received the greatest attention. In presenting the results of the study, I have included data and conclusions drawn from field experience, supplemented with laboratory examinations, and have attempted to co-ordinate these with existent knowledge. In addition, I have pointed out, and often quoted extensively from, relatively little-known papers that seemed to bear on certain particular aspects. Benton County is well situated for a study of this type. The county actually lies in somewhat of a huge basin. To the south, the Calapooia Mountains near Eugene provide an east-west mountain link between the Cascades and the Coast Range. High hills likewise connect these ranges in the latitude of Portland. These hills furnish dispersion routes between the two main mountain chains. From the standpoint of broad habitat types, the county includes, or is very close to, coastal forests, typical Coast Range, Coast Range foothills, and the Willamette Valley. There occur with certainty in Benton County 9 salamanders, 4 toads and frogs, 3 lizards, 6 snakes, and one turtle. In addition, there are doubtful records or the possibility of the occurrence of 3 toads and frogs, one lizard and 2 snakes. Each of these doubtful records or possible additions have been briefly discussed in order to indicate the status of our knowledge. Each of the known species of Benton County is presented in detail. Careful descriptions are given where it is felt that the literature is inadequate. Emphasis is placed on accurate identification of both adults and young. Distribution in Oregon is presented briefly, followed by a more detailed account of Benton County distribution, including locality records. A map for each species shows these data. Habitat preferences are discussed at length, with descriptions of particularly fruitful collecting sites included in many cases. All known phases of reproductive activity are discussed. Food and feeding are treated of where facts are known. A section on general habits deals with daily and seasonal movements and migrations, hibernation, enemies, voice, captivity and economic implications. Unsolved problems are suggested for each species. Photographs are provided for clarification of difficult identifications and…