PARAMETER POPULASI DAN SPAWNING POTENTIAL RATIO (SPR) KEPITING MERAH (Scylla olivacea) DI PERAIRAN ASAHAN DAN SEKITARNYA, SUMATERA UTARA - Pane, Andina Ramadhani Putri; Kembaren, Duranta Diandria; Marasabessy, Ilham; Suman, Ali (BAWAL Widya Riset Perikanan Tangkap, 2021)
Kepiting bakau merupakan komoditas ekspor yang penangkapannya dilakukan dengan intensif, salah satunya adalah jenis kepiting merah (Scylla olivacea). Pengelolaan dalam pengendalian memerlukan analisa kajian ilmiah tentang ukuran layak tangkap dan spawning potential ratio (SPR) kepiting merah. Kajian ilmiah ini dilakukan terhadap 1.105 ekor kepiting merah di pusat pendaratan kepiting di Desa Silo Baru Kecamatan Silau Laut Kabupaten Asahan, Sumatera Utara selama 28 bulan (April-Oktober 2018, Februari- Desember 2019 dan Maret-Desember 2020). Kepiting yang tertangkap memiliki ukuran 65-170 mm dengan 72,2% sudah dewasa dan telah melakukan pemijahan sebelum tertangkap (CWc< CWm). Hasil penelitian diperoleh bahwa kematian akibat penangkapan (F) lebih tinggi dibandingkan kematian alamiah (M), hal ini menunjukkan tingginya tekanan pemanfaatan (E = 0,54%). Nilai spawning potential ratio (SPR) mengalami peningkatan dari tahun 2018 ke tahun 2020 yaitu 11-17% namun masih dibawah nilai minimal 20%, artinya penambahan individu kepiting merah di perairan Asahan setelah ekspolitasi sudah mengalami penurunan sehingga diperlukan upaya dalam pengelolaan. Upaya yang dapat dilakukan adalah dengan meningkatkan ukuran mesh size jaring dan bubu serta rehabilitasi hutan mangrove.Mud crabs are export commodities that have been harvested intensively; one of which is the red mud crab (Scylla olivacea). Management in controlling its exploitation requires scientific studies on the analysis of the legal size and the potential spawning ratio (SPR) of the crab. In this scientific study, a total of 1,105 red mud crabs were analyzed at the crab landing center in Silo Baru Village, Silau Laut District, Asahan Regency, North Sumatra for 28 months (April–October 2018, February–December 2019, and March–December 2020). The crabs caught were 65–170 mm in size, where 72.2% of which were already adults and had spawned before being caught (CWc < CWm). The results of this study suggested that the fishing mortality (F) was higher than the natural mortality (M), indicating a high exploitation (E = 0.54%). On the other hand, the potential spawning ratio (SPR) from 2018 to 2020 kept increasing, i.e. 11–17% (below the minimum SPR 20%), indicating that the addition of the individual red mud crabs in Asahan waters after exploitation had decreased. Therefore, several efforts are necessary in its management, among others by increasing the mesh size of the nets and the size of the traps as well as rehabilitating mangrove forests.