He suffered frostbite , had a close encounter with a polar bear and pushed his body to the limit , hauling his supply-laden sledge up and over jagged ice ridges .
他忍受了叮咬,和北极熊为伍,强忍着身体的极限拉着他满载物资的雪橇走过崎岖不平的冰路。
Marine scientists measure its abundance by dragging a sledge equipped with video cameras along the seabed and counting the number of holes ( a well-maintained burrow being the sign of a happy prawn ) .