1924

DEPARTMENT OF THE INTERIOR NATIONAL PARK SERVICE YOSEMITE NATIONAL PARK.

Y OS.Fril TE NATURE 2222222 Aueus t 9. 1924 volume. t xosemito Mature Guide Service Number 15

C. P..Russell. Park Natur?li:J This is one of a series of. bulletins issued from time to time for the information of those interested in the natural history and scientific features of the nark and the educational opportunities the 'dark affords for the study of these subjjoots,. Utilization of these bulletins by those receiving them to the end that the information contained therein might be as extensively distributed as possible will be appreciated.. W. B. I.ewi s, Superintendent

LOW WATER KILLS PLR

Not only in Yosemite but all over the state the unusually low water in the streams is bringing death to trout. hs soon as a stream ceases to flow and the water Is left in pools, fish fail to get enough oxygen and smother to death, even if a hind fate saves them frooi starvation. On August 3 it was necessary to rescue a number of fish from Tenaya Creek just below Mirror Lake. The t'ater disappeared almost over night, and many fish died. To the naturalist it seemed strange that Loch Leven Trout, that thrive in the warmer, more slowly moving waters, were the first to die, whsreas most of the native Rainbow Trout, lovers of cold, rushing waters, survived until re sowed,

- OBSERVATIG:-:S OH NESTING V RITE-IMADED +OODPECHERS

Cihen I arrived here on Friday, June 6th, I found a family of Northern White-headed -ood_ eckers loc. ted in one of the corner posts at the front of the rangerstation. The entrance hole, which was about an inch and a half in diameter, was a little more than six feet above ground. The young were evidently just hato;F;, for a few weak chirps were all that could be heard. The old birds brought " f cub" at about ten minute intervals from daylieht to dark. After a week, it appeared that there was only one "chick' in the nest, His voice gained steadily in both volume and lasting quality, until at the end of two weeks he chirped almost constantly all day long. Figuring that he peeped;once a second, which is rather too slow, in eight hours he would peep a total of 28,000 timest Quite a large amount of food would be required just to keep his vocal chords vibrating] Contrary to the custom of lumberjacks, he enjoyed making the most noise when he was eating.

At first, pictures were possible only ith a tripping device, but during the last four or five days before the young one took flight, I could stand within three feet of the hole, and. have ti^e old birds come right don and feed him. They would be rather apprehensive at first, but as soon as the "chick" heard the sweep of wings, he would stick his head out and set up such a howl that they disregarded everything else and c !sme down to feed him. During this latter aeriod, his voice started to ohange. Every few mina utes the chirpiag-would give way to the characteristic staccato of the nature bird * He also began to e ::erci se his bill on the inside of the - post,,. 1f, a pencil or finger were held to the otening, he vould bradiauely attack, 141 these were signs that he would soon he leaving, anal. I_ was not surprised when on the morning of the 27th I found the nest *vacant-,---hilllahl LL. Harlow, Ranger at Aspen Valley.. AN Ili:TE 3 TIN BEHAVIOR GP etid -CCiES At this season of the year in Yosemite the cones of many of our conebearing trees offer extremely interesting objects of study" and observation. On a number of our Dines one may find cones of throe, ages : those which matured. and dropped their seeds in 1923, those which will mature in 1924, and those which reach maturity in the fall of 192.5. The last mentioned cones all point upward. This position is the one most likely to insure pollination. Some of the pollen, carried by the wind,-lodges boGneen the scales of the cone, and later fertilization_ takes place. After fertilisation the further growth of the cone results in its turning downward and becoming pendent, This behavior of the cone is due to the influence of gravity. Just how it is that gravi. cy, produces this result is not known, but it is definitely established that in some wa= y the "effect of gravity is to cause ties young cone to remain }o :?.nting upward until after fertilization takes place, and then the effect of gravity is to make tie cone turn dog -.ward, ~1H-+JL-YAHo ih-.wi-yah or ' "Quiet 'later" is much more musicel than the white =Ifs version liI irror Lake". The word rumor -is much in keeping with the chewing gum tokens and the paper Trail of the kodak that fringes the lake. We need simplicity, quietness, and the natural in our language and life. it is the quietness of the lake that enables us to see the reflection of Clouds t Rest. To see over a mile of granite ledge reflected in a small sheet of water is sufficient cause for musing. It is not until midday that the image is brushed away by the gentle,.eanyon breeze, iich ripples the surface. And this may give cause for further meditation. Our reverie may take.us back to the beginning of the lake. It was born long after the Glacier had scoured out the U-chapel walls of T.suaya Gorge. Geologists tell us that about three hendr.d years ago a severe earthquake shook the loose material from the v: all s of the cliffs of this region, forming the major part of our talus slopes. It is possible that during such a disturbance the. graded debris was thrown across Tenaya Creek to form Ahwi-;jah. - 2 w

ah,wi-yah was no sooner born than the creek set in to destroy it. Granite born soil, sand from the quartz, and clay from the feldspar, were dropped into the lake. Asthe deposits accumulated, the vegetation began to maroh into the shallow stretches of the upper end. a close study of this conquest of the lake will probably picture the filling; of the post-glacial Yosemite lake. Jbara and burr-reed are practically the only aquatics that have found this recent lake. This is probably due to the youthfulness of the lake and to the fact that there are very few aquatic plants in the lakes of the upper Penaya Creek, The sand plain, which has accumulated at the entrance of the creek into the lake, ?s being laid down factor than the vegetation can seed it * Sorrel is in the front ranks. This plant probably did not grow on the shores of Yosemite Lake r as it to a recent weed arrival from Euro pe. The next plant settler is a native Arter:esia, which ooudd have been the first colonise on the ancient lake. ':,Illow is in the front ranks of the woody battalion. Behind it in close formation are marching the lodgepole pines. In the open spaces are lu ine, mint, pussy paw, and natzanita.-, pioneer plants of dry areas and the chaparral, which have been well trained to meet the drought ccmditiora of this sand desert, Incense Cedar is not quite sc venturesome but appears in the back ranks of the leafy cover. As soon as the willows stabilize the stream banks, the black cotton wood and the creek dogwood take up the stand, each plant preparing the way for the one in back of it. Coming down to the shores of the old lake are, the black oak, yellow pines, and the firs. They have not yet ventured onto the lake plain but are evidently preparing to do so. The tree colonization is so rapid that the meadow stage is very briefe She animals which accom pany lakes are very few in ah wi-yah. This., too, is probable due to its youthfulness.. During this season it is unusually low. Along its clay margin are autographed the tracks of the spotted sand_.iper, deer which coma down to drink, and suer folks. In its deeper recessives are the native rainbow trout, A few rater striders walk along its surface, Taken all in all, its life is a solitary one. Not a frog. tc break the silence nor a turtle to sun himself upon a log. herein is being enacted in a short space of time the history of the Yosemite Valley. V-shaped valley, Glacier, U-shaped valley, dam, lake, neadow, shrubs, forest march in succession like a great play a the sand plain a stage, arid. the trees the actors. visitors to Yosemite should co to Ah-wi-yah, for therein is breathed the spirit of the Groat Valley.