Investigating the application of spawning shelter of Cattle fish for its enhancement of resources

Abstract

In this project,four types of structures,of 40 number was investigated.In a six month period,the structures were inspected 13 times.The total weight and number of eggs hatched on the structures were estimated to be 214.1kg and 94944 respectively.The weight and number of eggs settled on trap types were 141.9 and 60982 respectively,whereas,The eggs on cubical structures were estimated 56.7kg and 27088 ,on pyramid structures 7.9 and 3941 and then also were 6.9kg and 3280 eggs on cylindrical structures respectively.It is also estimated that 358 eggs were settled on The connecting line weighting 0.5kg.In this report four types of structures was compared.As a result,the trap, cubical, pyramid and cylindrical structures had contributed to the settelment of 66,27,4 and 3 percent of eggs in weight. While 64,29,4 and 3 percent of eggs in number was settled on these structures respectively.Thus it is concluded that the trap structures fallowed by cubical ones had acted more effectively relative to other two.If based on the results of other studies,we assume 80% survival rate of eggs and average weight of 1.2kg of survival growth cuttlefish , then it can be calculated that 160 structures can contribute to 91 tons increase in cuttlefish stock in one area of 4 to 5 acre.It is obviaus that by planning an annual increase of the structures,it is passible to attract more spawners to spawn and produce more larvae.Moreover,The old structures will be covered by corals and barnacles and become amore stalie and attractive spawning ground for cuttlefish.