In the winter the northeast seasonal winds blow strong and harsh, pushing sand and rocks into the northern outlet to the sea. The water thus flows out through the southern exit point. In the summer come the southeast seasonal winds, which blow silt into the southern outlet, so that the Hsiukuluan River heads north for the summer.
冬天東北季風強勁，將泥沙吹向北邊，堵住了北邊的出口，溪水於是由南邊出海；夏天吹東南季風，泥沙被吹向南邊出口，秀姑巒溪於是從北邊出海。