Biomorfometrik Rajungan (Portunus pelagicus) di Perairan Senggarang

Abstract

Rajungan (Portunus pelagicus) merupakan salah satu komoditas penting perikanan Indonesia. Perairan Senggarang Kota Tanjungpinang yang merupakan wilayah salah satu habitat rajungan. Tujuan penelitian ini adalah untuk mengetahui hubungan lebar karapas dan bobot, faktor kondisi, dan mengetahui morfometrik rajungan di perairan Senggarang. Penelitian ini menggunakan metode survey menggunakan teknik purposive sampling yaitu berdasarkan daerah tangkapan nelayan rajungan. Hasil penelitian menunjukkan jumlah rajungan jantan dan betina sebanyak 79 dan 56 ekor, sehingga diperoleh nisbah kelamin adalah 1,41:1. Hubungan lebar karapas dan bobot rajungan jantan diperoleh nilai b sebesar 3,3485 termasuk allometrik positif, sedangkan betina diperoleh nilai b sebesar 2,7142 termasuk allometrik negatif yang menunjukkan bahwa rajungan jantan lebih besar dibandingkan betina. Faktor kondisi rajungan jantan dan betina di perairan Senggarang memiliki badan yang kurang pipih atau montok. Status pertumbuhan morfometrik rajungan jantan dan betina bersifat allometrik positif sebanyak 14 karakter. Allometrik positif merupakan status hubungan yang menunjukkan bahwa pertambahan karakter lebih lambat dibandingkan pertambahan karakter morfometrik pembandingnya. Allometrik negatif sebanyak 10 karakter dan isometrik 1 karakter. Status hubungan karakter jantan memiliki hubungan sangat rendah (A4, A5, C3), sedang (B2, C2, C4, D3, D5), kuat (A2, A3, A6, B3, B4, C1, C5, C6, C7, C8, D1, D2, D4, D6, D7), sangat kuat (A1, B1). Karakter betina memiliki hubungan sangat rendah (D5), rendah (A5, B3, C2, D3), sedang (A4, A6, B4, C3, C6, C7, D1, D6, D7), kuat (C1, C4, C5, C8, D2, D4), sangat kuat (A1, A2, A3, B1, B2).

Blue swimming crab (Portunus pelagicus) is one of the important fisheries commodities in Indonesia. Senggarang waters, Tanjungpinang City, which is one of the crab habitats. The objectives of this research were to determine the relationship between carapace width-weight, condition factor, and morphometrices of the blue swimming crab (BSC) in Senggarang waters. The method uses an observational survey method using a purposive sampling technique that is based on the catch area of BSC. The results showed that there were 79 male and 56 female BSC, so the sex ratio was 1,41:1. The relationship between carapace width-weight of the male BSC obtained b value of 3,3485 (positive allometric), while the female obtained b value of 2,7142 (negative allometric) which indicates that the male BSC is larger than the female. The condition factor of male and female BSC in Senggarang waters has a body that is less flat or plump. The morphometric growth status of male and female BSC is positive allometric 14 characters, negative allometric is 10 characters, and isometric 1 character. The relationship status of male characters has a very low relationship (A4, A5, C3), moderate (B2, C2, C4, D3, D5), strong (A2, A3, A6, B3, B4, C1, C5, C6, C7, C8, D1, D2, D4, D6, D7), very strong (A1, B1). Female characters have a very low (D5), low (A5, B3, C2, D3), moderate (A4, A6, B4, C3, C6, C7, D1, D6, D7), strong (C1, C4, C5, C8, D2, D4), very strong (A1, A2, A3, B1, B2).