Hsu Kai-jung, 70, remembers that during the period of the Japanese occupation, the Japanese would come every year to worship at their Shinto shrines. They'd order aboriginal youths to pick trifoliate jewelvine, which would be ground up and dumped in the river. Poisoned zacco and other fish could be seen from the upper stretches of the Chingshui to the mouth of the Hsiukuluan.
七十歲的徐開榮則記得，日據時代日人每年十月祭拜神社，就令山地青年採「魚藤」，搗碎後傾入河中，由清水溪上游一路綿延到秀姑巒溪出海口，「都可以撿到被毒昏的溪哥等溪魚。」