Gonad Maturity Level of Lorjuk’s (Solen sp.) Population at the East Coast Surabaya

Lorjuk (Solen sp.) is Pelecypoda that have a high economic value the East Coast Surabaya. Currently Lorjuk abundance has begun to decline and stock enhancement efforts are required. This study aims to determine the part of the reproductive cycle in the form of determination Lorjuk Gonad Maturity Level (Solen sp.) Were arrested on the East Coast Surabaya. Taking a sample of 30 individuals was conducted in May-October 2012 with a time interval of 2 weeks. Observations made directly covering morphometry body length and body weight and diameter oocystnya Lorjuk. Gonad Maturity Level (GML) was conducted by observing and classifying gonad histology based on illustrations photomicrograph gametogenic scale at Ensis arcuatus. The relationship between the level of maturity of gonads with oocytes diameter Lorjuk follow equation GML=0522+0528 oocyte diameter with a correlation of 79.2. The results of these observations indicate that the level of maturity of Lorjuk’s gonad which is at a mature stage and the stage ready to spawn can be acquired in May-June.