39 Special Number 1 – 1951

notes

Volume 17 Special Number 1, 1951

All material courtesy of the National Park Service.These publications can also be found at http://npshistory.com/
Nature Notes is produced by the National Park Service. © 1951

Preface

By Dr. G. C. Ruhle, Editor

The author, Dr. Ralph Ruskin Huestis, during his summer vacations, has served, with several breaks in continuity, as a ranger naturalist in Crater Lake National park since the middle thirties. He was born in Bridgewater, Nova Scotia, on January 14, 1892, and received his BSA degree from McGill University in 1914. From 1914 to 1919 he served with the Canadian Expeditionary Forces. Entering the University of California for graduate work, he received a Master of Science degree in 1920, and completed his work for the degree of Doctor of Philosophy in 1924. At the same time, he served as assistant biologist at Scripps Institute in California. Since 1924, he has been a member of the faculty of the University of Oregon, and is now a professor of biology at that Institution. Professor Huestis has been celebrated for his ability to make natural history interesting, for interpreting science and scientific subjects in a language that the layman appreciates. This special bulletin is a reflection of that ability as well as a fine contribution to our knowledge of one of the most fascinating small mammals of the Park fauna.


“Rim wall in front of Information Building” as seen through the view window of the same.

The Golden-Mantled Ground Squirrel in Crater Lake National Park

By Ralph R. Huestis

The golden-mantled ground squirrel, Citellus lateralis chrysodeirus Merriam, is one of the commonest mammals in Crater Lake National Park and probably produces more entertainment for visitors than all other types combined. This is not only because these animals are aggregated along the rim and in the campgrounds, where the greatest concentration of visitors takes place, but also because the squirrels are handsome in appearance, readily conditioned to the presence of human beings, and both appealing and comical in their behavior.

This species is commonly present in forested regions of Oregon from the Cascade mountains eastward and is especially prevalent in the ponderosa pine forests of the Cascade, Blue, and Wallowa Mountains. It is found, in these regions, from the edge of the sagebrush up into the white-bark pines at 8000 feet altitude. At Crater Lake these squirrels are present in all regions of the park including both Wizard Island and, on one occasion, on the Phantom Ship. The race occupying the Siskiyou mountains and therefore present in the Oregon Caves National Monument is described as subspecifically distinct and called the tawney-mantled ground squirrel, Citellus lateralis trinitatus Merriam.

DESCRIPTION

The golden-mantled ground squirrel is a chunky little animal with a body about seven inches long and a well furred tail somewhat more than one-half the body length. Its legs are rather short and its ears relatively small but held tautly erect. The eyes are quite large for a burrowing animal and their size, combined with the erect carriage of the ears, give these squirrels an air of alertness and intelligence.

The flanks, the underside of the tail, and the head and shoulders are colored a rich, reddish brown. This is the coloring that accounts for the name golden-mantled. The back carries a broad median gray stripe, on each side of which are narrower contrasted stripes of black and white; two black ones with a white stripe between them. These contrasted stripes following the curve of the back while the squirrel sits up add greatly to its appearance.


“. . . contrasted stripes following the curve of the back . . .”

Ground squirrels are not very fast animals and this squirrel compares unfavorably in speed with the chipmunks that occupy the same territory and with small enemy carnivores like the Cascade weasel, the Pacific marten, and the Cascade red fox. There is, however, an alertness in its postures and a briskness and energy in its movements that visitors find attractive. It seems probable that the hurried gallop from point to point which the squirrels alternate with a frozen pose or a brief nosing of the ground is highly adaptive. An animal in motion is likely to be seen and had better hurry if it moves at all. In addition, the time spent on exposed territory and between feeding periods is reduced to a minimum. These points may not be obvious to visitors, but they do see a hard-working little animal and admire the display of energy.

Comedy is supplied by the fact that the air of brisk alertness is not accompanied by any real evidence of great intelligence. In fact Citellus not infrequently plays the role of a busy fool; searching industriously for peanuts in empty hands when full ones beckon, and taking the trouble to investigate with a passing sniff any little object which may lie in his pathway on the rim walk pavement. He easily changes, too, from assured approach to precipitous flight with his tail above his back at about the angle a stove lifter projects from the lid, his broad little hams twinkling as his short hind legs spurn the dust.