Stone reef fishing is a kind of Compulsory Trap Fishing at the tidal zone.  After the ebb and there is flooded pond, fish can be caught at hand.  Xi-yu township doesn’t possess superior condition to build stone reef, there are total 142 stone reef belonged to eleven villages.  The Xiao-chi-jiao of Chi-dong village and Chi-xi village have the most number of stone reef.  Curve rock dike to be in the majority of the stone reef mould/type, reaching a total of 101 and occupying 72% of all the stone reef in the township.Except for Er-kan, Xiao-chi-jiao, Da-chi where there are large-sized stone reef, others are small-scaled dustpan stone reef.  Owing to a nearly zero amount of catches, in addition to the flourishing of inshore fishing, stone reef now are mostly abandoned and half of them are worn-out.