The river's green water weeds and water plants, together with the fish, shrimps and aquatic insects that shelter in its rock pools, provide nourishment for these distant southern migrants who thus build up their strength each year for the long journey back north.
石塊堆疊成的小水窪深藏魚、蝦、水生昆蟲，布滿水域內的綠色水草、各種水生植物，供養千里迢迢南來的雁鴨，年年它們得以補足體力，安然北返。