Pengaruh Kepadatan Terhadap Tingkat Kematangan Gonad dan Fekunditas Kepiting Bakau (Scylla serrata) pada Kultivasi di Tambak Garam

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Penelitian ini bertujuan untuk mengetahui kematangan gonad dan fekunditas kepiting bakau (Scylla serrata) dengan sistem kultivasi dalam karamba di tambak garam berdasarkan perlakuan kepadatan benih yangberbeda.Benih kepiting berjumlah 144 ekor dengan berat awal rata-rata 250 gram, terbagi kedalam empat perlakuan kepadatan, masing masing A ( 6 ekor ), B ( 8 ekor ), C ( 10 ekor ) dan D ( 12 ekor ), yang masing– masing diulang empat kali dipelihara dalam karamba berukuran 1 x 0,75 x 1 meter. Pemeliharaan dilakukan selama 2 minggu ( 8 – 23 Oktober 2001 ). Hasil pengamatan kematangan gonad berdasarkan dianalisis berdasarkan Indeks Kematangan Gonad serta fekunditas. Kematangan gonad kepiting bakau Scylla serrata tercapai secara merata dengan indeks berkisar diantara 42.87 – 68.70, dengan indeks tertinggi sebesar 65.12 ± 2.39 pada perlakuan C ( kepadatan 10 ekor per 0.75 m 2 ). Sedangkan fekunditas berkisar diantara 60000 –120000 butir telur, dengan perlakuan tertinggi dicapai pada perlakuan B dengan kisaran jumlah telur 96000 – 120000 dan nilai rata – rata 110000 ± 12000 butir telur. Hubungan berat kepiting dengan fekunditas total Y = 567.9562 – 103477.337 X ( r = 0.7966 ). Fekunditas memberikan hasil linier menurun berdasarkan perlakuan dikarenakan kemampuan toleransi serta ruang gerak yang terlalu sempit dan persainganKata kunci: kepadatan, kematangan gonad, fekunditas, kepiting Scylla serrata.The aim of the research is to know the effect of different density on the gonad maturity and fecundity of mud crab ( Scylla serrata ) grown in the cage. This cage were put in salt water pond. Four treatments (density ), i.e. A ( 6 individual ), B ( 8 individual ), C ( 10 individual ) and D ( 12 individual ), with four replications, were applied. The average initial weight of the mud crab is 250 gram. These were grown for two weeks ( October 8 to 23, 2001 ). The mud crab gonad maturity and fecundity was analysed using the analysis based on the Gonad Maturation Index and Fecundity. The gonad maturity was found for almost of mud crab Scylla serrata. The gonad maturity index showed a value from 42.87 – 68.70, which the highest was reached by the treatment C ( with the density 10 individual per 0.75 m 2 ). The fecundity varies from 60000 –120000 eggs, which the highest was 110000 ± 12000 and reached by the treatment B ( with the density 10 individual per 0.75 m 2 ). The relationship between mudgrab weight and fecundity was Y = 567.9562 – 103477.337 X (r = 0.7966). The fecundity showed a decreased linierity due to the limitationspace cause by the level of density.Key words: density, gonad maturation, fecundity, mud crab Scylla serrata