Nature Notes From Crater Lake
Volume 17, 1951
Research on Salamanders
By James Kezer, Ranger-Naturalist
(Research is a vital part of the
activity of the naturalists in our National Parks. It is the source of
knowledge about what is in the park and what is occurring. Its results
furnish the supply of information which the park needs to interpret its
treasures for the public. Only by continuous study of problems with full
possession of facts can intelligent administration and operation of the
park be achieved. The pursuit of research is a stimulus which keeps
fresh and vigorous the enthusiasm of the naturalists in their lectures,
guided trips afield and other efforts. - Ed.)
During the summer of 1951, Dr. Donald
S. Farner and I carried out intensive field work on park amphibians and
reptiles. We were ably assisted by our fellow ranger-naturalists as well
as by Lawrence Bisbee of the fire suppression staff, Fred Larmie of the
ranger staff, and Roy Strand of the trail crew. Lawrence Bisbee made the
first big discovery of the summer by collecting a specimen of the Oregon
red salamander,
Ensatina eschscholtzii oregonensis (Girard), from beneath a pile of
boards near Annie Spring on August 7, at an elevation of 6080 feet. This
is the first specimen of this salamander to have been found in the park
and it is apparently the highest altitude record for any member of its
genus. Although the specimen has been allocated to oregonensis,
it is actually intermediate between oregonensis and platensis
(Espada), according to the recent revision of Dr. Stebbins of the
University of California. A thorough search of the area in which this
salamander had been collected, failed to reveal other individuals. It is
possible that others will be found in the park, if looked for earlier in
the season when the ground contains a greater amount of moisture.
A second important addition to the
herptofauna of the park occurred on September 15 when Lawrence Bisbee,
Fred Larmie and I found the northwestern salamander, Ambystoma
gracile Baird, occupying bog ponds in the vicinity of Crater Spring
at an altitude of 5300 feet. The three ponds in which this salamander
was first found are in the rarely visited northwestern section of the
park, about one-half mile south of the end of Crater Spur Motorway. Two
of these ponds are small, not more than six feet in diameter, but the
third is larger -- about 25 feet long and 10 feet wide. Each pond is
surrounded by a floating mat of vegetation and the sides drop off almost
vertically to a depth of four to six feet. From these three small bodies
of water, we collected nine large larvae which have a mean total length
of 165 mm. These larvae, although unmetamorphosed, are sexually mature
and were breeding in the larval condition. This curious situation,
neoteny, is oftentimes found in this and certain other species of
salamanders.
Along the northern side of Crater
Creek, I found A. gracile
occupying a bog pond that was almost filled with vegetation. Large
larvae of this species were seen in this pond; however, my collection
consists of two smaller individuals.
In the vicinity of the park, Norman
Davidson and I collected A. gracile in a cut-off section of the
Rogue River below Hamaker Meadows and Philip Ross and I discovered it
making up part of an abundant salamander fauna in Spruce Lake, an
isolated montane pond at 4750 feet in Jackson County, a mile and a half
from the western boundary of the park. The lake is about 200 yards long,
30 yards wide and approaches a maximum depth of eight feet. It supports
an abundant population of A. gracile, associated with the Oregon
newt,
Triturus g. granulosus, and the long-toed salamander, Ambystoma
macrodactylum. The isolated and undisturbed nature of this body of
water along with its large salamander population make it an ideal place
for the study of this species. My several visits to this pond, during
the first two weeks of September, revealed an A. gracile
population made up of large neotenic larvae, smaller larvae of several
size classes, metamorphosing larvae, and completely metamorphosed
individuals.
In each of the four localities where
this salamander has been collected, its globular egg masses have been
conspicuous. On July 25, in the cut-off portion of the Rogue River,
hatching had already taken place in some of the egg masses but in others
the embryos were present in the gel. At Spruce Lake on August 31, at
least 150 masses of gel were seen, hatching having taken place sometime
prior to that date. On September 22, I was extremely pleased to find an
egg mass of this species containing well-developed embryos in a small
bog pond along the northern side of Crater Creek. Along with the various
size-groups of small larvae that have been found in Spruce Lake and in
the bog ponds near Crater Creek, this unhatched egg mass indicates a
long egg-laying season for this species.
The salamander for which Crater Lake
National Park is zoologically famous is the Mazama newt, Triturus
granulosus mazemae Myers, a "water dog" that is found no place in
the world except in the waters of Crater Lake. It is closely related to
the common Oregon newt,
Triturus granulosus granulosus (Skilton), but differs in having
varying amounts of dark pigment mixed with the orange or yellow of the
under surface. Dr. Farner and I were unable to find specimens of
Triturus that had been collected in the park other than from the
lake. We were interested in securing newts outside of the lake, but near
it, in order to see if they would be ordinary granulosus or the
much less common mazamae. Accordingly, the two of us were
delighted to find a single large adult newt on August 25, in a cut-off
oxbow along Munson Creek. We examined it carefully, finding no evidence
of any of the characters which distinguish mazamae from typical
granulosus, despite the fact that it had been collected only two
and one-half miles from Crater Lake. Two more specimens of typical
granulosus were collected September 22 in the bog pond near Crater
Spring which was mentioned previously in connection with Ambystoma
gracile. We believe that these collections of typical T.
granulosus within the park, but outside of the lake, give strong
evidence toward the idea that the Mazama newt is a subspecies entirely
confined to Crater Lake.
These brief notes give an idea of
progress made during 1951 in our understanding of the herptofauna of the
park. For those particularly interested in this group of animals,
detailed information about the amphibians and reptiles of the park has
been prepared for publication sometime during the coming months.