Report 10718: Campers hear a vocalization near Tenaya Lake

Some friends and I were camping in Yosemite Park in the fall of 1976. At about 10:00 P.M. we were in our sleeping bags in the tents talking when all the animal sounds going on around us suddenly went quiet. Then we heard a loud , low scream that gradually ended in a high pitch. All of us sat up and were asking the usual question ," what was that ?", then as we waited in our tents we heard other campers from around the lake talking and walking our way when we looked out of the tents we saw that they had all there stuff with them and were leaving in a hurry. We asked them what that noise was and they asked us if we had seen the thing run by our campsite ....we were too scared to notice I guess...We watched your special on cable this morning and when they played the vocalizations of what is beleived to be a Bigfoot  I got scared all over again this many years later. The only difference was that what we heard ended in an abrupt higher pitch.