The pilot had been carrying out a solo cross-country training flight, when deteriorating lift forced him to make an outlanding. The approach to the paddock selected involved passing over a line of high trees. Severe sink was encountered and the pilot realised he would not clear the trees. He therefore applied full spoilers and attempted a landing short of the planned area. During the landing roll the glider collided with a flock of sheep, killing five of the animals on impact. The pilot was a Japanese national who was visiting the area. Before DEPARTURE he had advised the soaring club that he wished to undertake a local flight. As a result, he was not briefed on cross-country procedures and outlandings. When thermals were encountered after take-off, he had elected to conduct a longer flight. When the outlanding became necessary, the pilot had misjudged the strength of the wind and had continued downwind beyond the point where a successful approach to the selected paddock could be made.