ASPEK BIOLOGI UDANG Metapenaeus conjunctus DI PERAIRAN BATANG DAN KENDAL, JAWA TENGAH (Biological Aspect Assessment of Metapenaeus conjunctus Shrimp on Batang and Kendal Waters, Central Java)

Abstract

Udang penaeid di perairan utara Jawa banyak tertangkap nelayan, salah satunya udang Metapenaeus conjunctus. Jumlah produksi udang M. conjunctus di perairan Kendal dan Batang tidak tercatat dengan baik, karena tidak semuanya dilelang. Penangkapan udang menggunakan jaring arad dengan mesh size 19,05 mm. Perlu dilakukan pengkajian terhadap aspek biologi udang M. conjunctus di perairan Kendal dan Batang. Tujuan penelitian ini adalah mengetahui aspek biologi dari udang M. conjunctus di kedua perairan tersebut. Hasil penelitian tersebut dapat digunakan untuk menduga status stok sumberdaya udang M. conjunctus. Pengambilan sampel penelitian dilakukan di TPI Bandengan Kendal, TPI Tawang Kendal, dan TPI Roban Batang pada September 2016 - Januari 2017. Metode yang digunakan adalah metode survey. Sampel yang diambil sebanyak 10% dari total hasil tangkapan dalam sekali penangkapan. Data primer yang dikumpulkan yaitu data panjang karapas dan panjang total, berat udang, TKG, dan mesh size. Hasil penelitian menunjukkan udang betina jauh lebih banyak jumlahnya dibanding udang jantan baik di perairan Kendal maupun perairan Batang. Nilai L_50% udang jantan 77 mm dan udang betina 73 mm. Sifat pertumbuhan udang jantan di perairan Kendal bersifat allometrik negatif dengan nilai b = 2,881 dan udang betina bersifat isometrik dengan nilai b = 3,029, sedangkan di perairan Batang udang jantan dan udang betina bersifat isometrik dengan nilai b = 2,911 dan b = 3,033. Nilai faktor kondisi udang jantan dan betina rata-rata memiliki kemontokan yang sama. Udang jantan dan betina di perairan Kendal 1,089 dan 0,845, sedangkan di perairan Batang untuk udang jantan 0,827 dan udang betina 1. Udang M. conjunctus belum ada yang matang gonad.

Penaeid shrimp in Java's northern waters was caught by many fishermen; one of them is Metapenaeus conjunctus shrimp. The number of M. conjunctus shrimp production in Kendal and Batang waters is not well recorded, because not all of them are auctioned. Catching shrimp is using arad net with mesh size 19,05 mm. An assessment of the biological aspects of M. conjunctus shrimp in Kendal and Batang waters is required. The purpose of this research is to know the biological aspects of shrimp M. conjunctus in both waters. The results of  this study was to determine the stock status of shrimp resources M. conjunctus. The sampling was conducted at TPI Bandengan Kendal, TPI Tawang Kendal, and TPI Roban Batang in September 2016 - January 2017. The method used was survey method. 10% of total catch in one catch was taken as a sample. The primary data collected were data of  length of carapace and total length, shrimp weight, TKG, and mesh size. The result showed that female shrimp is much more numerous than the male shrimp both in waters of Kendal and Batang waters. The L50%’s value of male shrimp is  77 mm and female shrimp  is 73 mm. The characteristic of male shrimps growth in Kendal is allometric  negative with b = 2,881 and female shrimp is isometric with b = 3.029, while in the Batang the male shrimps and female shrimps are isometric with b = 2,911 and b = 3,033. The value factor of the male and female shrimp condition on average has the same plumage. Male and female shrimp in Kendal waters 1,089 and 0.845, while in Batang waters for male shrimp 0.827 and female shrimp 1. M. conjunctus shrimp has not been ripe gonad.