(Salmo rivularis)
The history of the so-called steelhead trout and the efforts to class
these sea-run fishes as a species separate from the rainbow and the
cutthroat, is interesting, if not amusing. No one questioned that they
were other than the sea-run of the rainbow or the cutthroat, according
to the locality, until Dr. Richardson, mistaking a young blue-back
salmon for a so-called steelhead gave it the scientific name of =Salmo
gairdneri=, and the description of this young salmon was recognized as
that of the steelhead for years, and under this name it appears in
the statutes of California, with a separate season for its protection.
In other words the =Salmo gairdneri= of the laws of California is a
young blue-back salmon and not a sea-run trout of any kind. Recently
Dr. Ayers to correct the mistake, examined a fish taken from the
Sacramento river and said to be a steelhead, gave it the name of
=Salmo rivularis=, and this now stands as the scientific name of the
so-called steelhead. Dr. Jordan, in an article recently published in
the Pacific Monthly, says: "There has been much discussion as to
whether the steelhead is a species really distinct from the rainbow
trout, and on this subject the writer (Jordan) has at different times
held different opinions."
If one authority bases his reasons for a belief in a specific
difference between the rainbow and the steelhead on the fact that he
did find a difference between a blue-back salmon and a rainbow, and
another authority finds so little difference that he holds different
opinions at different times, can there be any wonder that the
practical angler, who catches these sea-run fish at the mouths of our
rivers in every stage of transition, or gradation, if you please, from
the typical rainbow to the Simon pure steelhead, refuses to believe
that there is a specific difference?
Then again, Messrs. Jordan and Evermann in bulletin 47 of the United
States National Museum, "The Fishes of North and Middle America," say:
"In the lower course of the Columbia they (the steelhead) are entirely
distinct from the cutthroat or clarki series, and no one would
question the validity of the two species. In the lower Snake river and
other waters east of the Cascade range, the two forms or species are
indistinguishable, being either undifferentiated or else inextricably
mixed."
From this it would seem clear that the steelhead of the Columbia,
where the cutthroat abounds, are cutthroats that have gone to the sea,
grown larger in the larger body of water--a natural condition of all
fishes--and changed in color and appearance. That while they are yet
in the lower Columbia and only recently from the salt water, they
still maintain a sufficient difference to be easily distinguished from
the cutthroat; but by the time that they have reached the "Snake river
and other waters east of the Cascade range," their long residence in
the fresh water has again restored them to their former appearance.
The same changes are found with the rainbow and the steelhead of
farther south. All trout are anadromous to greater or less extent,
unless actually landlocked or living in streams so distant from the
sea that they would be compelled to pass through long stretches of
warm and sluggish water to reach it. The small trout of the coast
streams are compelled to go to the ocean quite early in the season by
the falling of the water to such an extent that in many cases the
streams go dry before the beginning of the winter rains, and in the
larger body of water they rapidly increase in size. The steelhead of
the Columbia river always retains the cutthroat sing-manual, to
greater or less extent, while the steelhead of the lower coast has no
red on the jaw. The claim that the smaller head of the steelhead is a
distinguishing mark, fails in effect, for it is an undisputable fact
that the older and larger the trout the smaller becomes the relative
size of the head. The other claim that the larger scales of the
rainbow is a distinguishing feature from the steelhead is not founded
on facts. For while the scales of the rainbow counted along the
lateral line vary from as low as 120 in the coast streams, they run as
high as 150 in the same streams, as high as 160 in the McCloud and 185
in the Kern. The average being 135 in the smaller coast streams, 150
in the Sacramento basin, and 170 in the Kern. The steelhead's scales
run from 130 to 155. An average of 145; or exactly an average of those
of the coast streams and the Sacramento. Were it possible for the Kern
river trout to enter the ocean no doubt we would find steelhead
running as high as 185 to the section.
Whatever may be the origin of the large sea-running trout called
steelheads, the fact remains that it is a grand fish both in size and
fighting qualities. In the ocean it eagerly takes the spoon and fights
with a vigor not even surpassed by the rainbow of the streams. After a
short sojourn in the fresh waters it rises to a fly just as readily.
Since the above was written Dr. Jordan has made the statement
publicly, that he is thoroughly convinced that the rainbow trout and
the so-called steelhead are one and the same fish; the only difference
being that the latter has grown larger and changed its color during
its life in the salt water, this variation of color returning again
after a short sojourn in the fresh water streams, giving it all the
original appearance of the rainbow, or of the cutthroat, as the case
may be.