- 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 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 for elucidation of various habitats.