Nature Notes

Volume VI No. 1 - April, 1933

Graupel -- The Soft Hail Of Meteorologists
By D. S. Libbey

It is natural that the many forms which falling snow assume should be displayed in such a nival region as Crater Lake. One of the odd forms is graupel. It is little pellets of compact snow --- miniature snow balls -- ranging from the size of coarse shot to that of small peas. Meteorologists formerly called it "soft hail", though it is crumbly rather than soft.

The graupel which falls at Crater Lake is mixed with soft snow. It appears that large wet flakes form and become involved in "traffic jams" up in Cloudland. As the masses come on down through cooler layers of atmosphere they freeze and they crumbly graupel aggregates result.

The Tule Fog Of The Klamath Basin
By D. S. Libbey

The Klamath Basin with its upper and lower Klamath Lakes and Agency Lake presents a very interesting phenomenon concerning fog conditions. It is most prevalent during the winter months but also occurs in the late evening and early morning hours for the warmer periods of the year. The fog is due to radiation of heat with the attendant ascending water vapor from the extensive water surfaces and adjacent tule swamp lands.

The depth of this so-called Tule Fog mantle is a variable but usually it is quite shallow. As a rule the fog disappears by midday -- the daily period of maximum sun insolation. On the other hand there are days and in some cases longer periods of continuous fog with the resulting poor visibility.

Chisel Teeth
By E. W. Count, Ranger Naturalist

Having been bitten in desperation by one of our Gilded Ground Squirrels - she was a lady, too - I was left to soliloquize on the potency of chisel teeth.

The wounds - two little punctures on the last joint of my middle finger- were 1-1/2 cm apart. Either both upper incisors had teamed to make one hole, and the lower likewise, or else only the teeth of the right jaws had been engaged. From the size of the holes, I should have judged the latter to be more probable.

Now, here was the interesting matter. The laceration from the upper jaw was slight: hardly more than an indentation. The (tooth) had struck glancingly. But the lower tooth or teeth had penetrated more deeply.

And there is a reason, which any one can ascertain by watching the little rodents at their chewing. It has been illuminating to note carefully one of my small beneficiaries trying to "stow away" a pear. The head is worked in such a way as to push the lower jaw up into the bite, the upper teeth acting, apparently, more as a hold or a bracer.

sketch of rodent skull

Then, if you examine a skull of a rodent, the cause becomes obvious (see sketch). The teeth of the lower jaw are longer and slightly heavier than those of the upper. The lower jaw used the same leverage scheme as that of any other animal's jaw - including man's: the fulcrum, a ball working in a socket, is shown at A. Strong muscles spread fanwise from the blade B to attach to the sides of the skull. (They are the same as the muscles one may feel swelling in the temples when he grinds his teeth.) But in the rodent, the leverage is greater and the muscles are relatively more powerful than in man. Furthermore, strong muscles run back from the skull (at C) to attach to the upper side of the neck vertebrae. As the squirrel gnaws, these may be seen rippling under the heavy skin of the nape.

A squirrel's head is an astounding thing in more ways than one. At the Lodge seventy-two Spanish peanuts were counted as they were solemnly stuffed at one sitting into the cheek pouches of one busy-tailed little scrambler.


On March 29 the snow depth at the Headquarters in the park reached 171 inches, exceeding the maximum depth of 166 inches for last year which occurred in early April.

The winter of 1932-33 appears to be a record-making one for Crater Lake. Already the depth of packed snow and ice exceeds the record of last year and it is very probable the total snowfall for the season will exceed that of last year.

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