The 4 objects moved very rapidly from east to west, then dissappeared.We were camping at Spicer Reservour just below Bear Valley, CA with another couple. My friend and I decided to go fishing in his small boat about 0700. We motored out across the lake to begin trolling. After a while his motor stopped running. As he was fixing his fishing pole, I began to hear a faint Jet engine sound approaching. Because I am a pilot and work in aviation, I always look up to indentify aircraft. The sound was approaching from the east and behind me. I looked and followed the sound but saw nothing. I continued until the sound was overhead. This is when I saw the ball shapped objects side by side. They were probably 1,000 ft AGL, moving at maybe 200 to 250 KTS or faster. They were aircraft aluminum in color. They all moved independently of each other and appeared to be trying to stay side by side at the same speed. My friend then looked but did not see them. He did hear the sound. They continued to the west for about 1 more second, then dissapeared