Biomorfometrik Kepiting Bakau (Scylla sp.) Hasil Tangkapan di Perairan Semarang Guna Menunjang Konservasi Sumberdaya Hayati

Abstract

Kepiting bakau (Scylla sp.) merupakan komoditas perikanan yang memiliki nilai ekonomi tinggi. Permintaan terhadap komoditas kepiting dari tahun ke tahun cenderung meningkat, sehingga dalam memenuhi semua permintaan ini seluruhnya berasal dari hasil tangkapan di alam, yaitu sebesar 70% dan banyaknya penangkapan kepiting bakau tanpa memperhatikan ukuran yang layak tangkap. Penelitian ini bertujuan untuk mengkaji biomorfometrik kepiting bakau, meliputi jumlah, distribusi, nisbah kelamin, hubungan lebar karapas dan berat, faktor kondisi dan tingkat kematangan gonad. Penelitian menggunakan metode deskriptif eksploratif. Penelitian dilaksanakan pada bulan  Mei – Juni 2017 di kawasan perairan Semarang, yaitu di Mangkang Wetan, Tapak, Tanah Mas dan Tambak Lorok. Hasil penelitian menunjukkan, bahwa jumlah kepiting bakau yang diamati sebanyak 616 ekor, terdiri atas 362 betina (58,77%) dan 254 jantan (41,23%), perbandingan betina dan jantan 1,43 : 1. Ukuran lebar karapas berkisar antara 47,05 - 132,56 mm dengan berat berkisar antara 33,02 - 513,09 g. Hubungan lebar karapas dengan berat bersifat allometrik negatif dan positif. Nilai faktor kondisi yang didapatkan berkisar 1,368 – 9,752. Tingkat kematangan gonad kepiting betina maupun jantan didominasi oleh TKG II dan III, dengan demikian diduga pada bulan Mei – Juni di perairan Semarang sedang terjadi masa pemijahan.

Biomorphometry of Mangrove Crab (Scylla sp.) Catched in Semarang

Mangrove crab (Scylla sp.) is one of the fishery commodities that have high economic value. The demand for crab commodity from year to year tends to increase, in order to fulfilling all these demands almost all of them come from the catch in nature that is equal to 70%, and this led to the occurrence of a lot of mangrove crab catching regardless of the size of the catch. This study aimed to examine the biomorphometric of mangrove crab, which includes the composition, sex ratio distribution, widht and weight relation, condition factors and gonad maturity level. The descriptive explorative methods was used in this research. This research was conducted from May - June 2017 in the Semarang waters included Mangkang Wetan, Tapak, Tanah Mas and Tambak Lorok. The results showed that the composition of mangrove crab were 616, consist of 362 females (58,77%) and 254 males (41,23%), with the comparison of female and male ratio of 1,43 : 1. The size of the obtained carapace width ranged from 47,05 - 132,56 mm with the size of the weight ranged from 33,02 – 512,09 g. The relations between width and weight of caparace indicated allometric. The value of the obtained condition factor ranged from 1,368 – 9,752. Gonad maturity level of male and female mangrove crab was dominated by TKG II and III, because the research location was in the spawning period.