KINERJA PRODUKSI DAN ANALISIS FINANSIAL PENDEDERAN PASCAPUERULUS LOBSTER PASIR (Panulirus homarus) PADA KEDALAMAN YANG BERBEDA

Abstract

Keberhasilan budidaya lobster bergantung kepada ketersediaan benih yang dihasilkan dari pendederan. Informasi teknologi pendederan untuk menciptakan kondisi lingkungan yang optimal bagi pertumbuhan dan tingkat kelangsungan hidup lobster masih terbatas. Kedalaman perairan merupakan salah satu parameter hidro-oseanografi yang berhubungan dengan suhu, intensitaas cahaya, tekanan, dan kesuburan perairan yang akan berdampak kepada fisiologis, pertumbuhan, dan kelangsungan hidup lobster. Penelitian ini bertujuan untuk menganalisis pengaruh kedalaman perairan yang berbeda terhadap kinerja produksi dan kelayakan finansial kegiatan pendederan pascapuerulus lobster pasir (Panulirus homarus). Penelitian menggunakan rancangan acak lengkap, tiga perlakuan kedalaman (1, 3, dan 6 m) dengan tiga ulangan. Pascapuerulus lobster pasir (panjang total 2,14±0,04 cm/ekor, panjang karapas 0,86±0,06 cm/ekor, dan bobot 0,28±0,04 g/ekor) yang telah dikarantina dan diadaptasikan ditebar ke dalam karamba jaring yang ditempatkan pada kedalaman tersebut di atas, dengan kepadatan 100 ekor/m3 atau 100 ekor/karamba. Karamba jaring berbentuk silinder (tinggi 0,8 m, Ø 1 m), terbuat dari rangka besi 10 mm dan jaring PE dengan mesh size 1 mm (bagian dalam) dan 5 mm (bagian luar). Selama 126 hari pemeliharaan, pascapuerulus lobster pasir diberikan pakan buatan satu kali sehari pada pukul 16.00 – 17.00 WIB sebanyak 15% biomassa/hari pada 60 hari pertama pemelihraan dan 20% biomassa/hari pada hari ke-61 hingga hari ke-126 pemelihraan. Pakan diberikan melalui penyelaman dengan bantuan peralatan selam dan snorkling. Setiap 14 hari sampel pascapuerulus sebanyak 30 ekor diukur bobot dan panjangnya untuk menghitung pertumbuhannya. Sampel glukosa hemolim pascapuerulus lobster diambil pada hari ke-0, 63, dan 126 pemeliharaan. Suhu, pH, oksigen terlarut (dissolved oxygen), dan salinitas air pada kedalaman 1, 3, dan 6 m diukur secara insitu setiap hari pada pukul 08.00, 12.00, dan 16.00 WIB. Biologi, intensitas cahaya, dan tekanan hidrostatik air diukur pada hari ke-0, 63, dan 126 pemeliharaan. Hasil penelitian menunjukkan parameter fisika-kimia air selama percobaan pada ketiga kedalaman masih berada pada rentang sesuai untuk pemeliharaan pascapuerulus lobster pasir. Seiring bertambahnya kedalaman, kandungan oksigen terlarut semakin menurun, namun masih berada pada rentang kebutuhan hidup pascapuerulus lobster pasir. Kedalaman berpengaruh terhadap intensitas cahaya, dan tekanan hidrostatik. Air laut pada kedalaman 6 m memiliki intensitas cahaya dipagi hari yang lebih rendah, yaitu 449±230 lux (P<0,05), namun tidak berbeda pada semua kedalaman disiang hari. Intensitas cahaya kedalaman 6 m (365±180 lux) berbeda dengan 1 m (1.116±335) (P<0,05), walaupun pada kedalaman 3 m dan 6 m tidak berbeda, begitu juga 1 m dan 3 m. Kedalaman 6 m menghasilkan tekanan hidrostatik tertinggi (P<0,05), rata – rata sebesar 1,628±0,015 atm. Kedalaman berbeda berpengaruh terhadap respons stres pascapuerulus lobster pasir. Konsentrasi glukosa dan THC terendah terdapat pada kedalaman 6 m, masing – masing 14,14 mg/100 mL dan 1,81 × 104 sel/mm3 (P<0,05). Kedalaman berbeda juga berpengaruh terhadap parameter kinerja produksi pascapuerulus lobster pasir, yaitu TKH, LPBS, LPBM, LPPS, LPPM, PPM total, PPM karapas, frekuensi molting, KKP karapas, RKP, dan biomassa total (P<0,05). Nilai TKH kedalaman 6 m lebih tinggi (71,00±2,00%) dibandingkan kedalaman 1 m dan 3 m (41,67±2,08% dan 43,67±3,06%). Tetapi nilai LPBS, LPBM, LPPS, LPPM, PPM total, PPM karapas, frekuensi molting dan KKP karapas kedalaman 1 dan 6 m tidak berbeda, namun lebih tinggi dengan 3 m. Nilai RKP kedalaman 6 m tidak berbeda dengan 1 m, namun lebih rendah pada 3 m. Biomassa akhir kedalaman 6 m memiliki nilai tertinggi (526,08±63,52 g) dibandingkan 1 dan 3 m. Usaha pendederan pascapuerulus lobster pasir kedalaman 6 memberikan keuntungan lebih tinggi, break event point (unit dan Rp), R/C ratio, dan harga pokok produksi lebih baik dibandingkan kedalaman 1 m dan 3 m. Selanjutnya, kedalaman 6 m layak untuk dijalankan berdasarkan analisis kriteria finansial (NPV, Net B/C, IRR, dan PP), sedangkan kedalaman lainnya tidak layak. Analisis sensitivitas hanya dilakukan pada kedalaman 6 m yang layak investasi. Penurunan TKH hingga 62,96% atau sebesar 11,28% cukup sensitif terhadap usaha pendederan pascapuerulus lobster pasir. Tingkat kelangsungan hidup berpengaruh terhadap keuntungan usaha (P<0,05). Begitu juga jika terjadi kenaikan harga puerulus mencapai Rp10.676 per ekor (48,63%), sensitif terhadap usaha pendederan kedalaman 6 m. Kenaikan harga pakan justru tidak sensitif terhadap usaha pendederan kedalaman 6 m. Pendederan pascapuerulus lobster pasir pada karamba jaring dengan kedalaman 6 m memberikan kinerja produksi terbaik dan paling untung serta layak untuk dikembangkan.

The success of lobster aquaculture depends on the availability of seeds produced from rearing activities. Information on rearing technology to create optimal environmental conditions for lobster growth and survival rates is still limited. Water depth is one of the key hydro-oceanographic parameters that influence temperature, light intensity, pressure, and water fertility, all of which affect the physiological state, growth, and survival of lobsters. This study aimed to analyze the effect of different water depths on the production performance and financial feasibility of post-puerulus rearing activities of sand lobster (P. homarus). The study used a completely randomized design with three depth treatments (1, 3, and 6 m) and three replicates. Sand lobster post-pueruli (total length 2,14±0,04 cm/individual, carapace length 0,86±0,06 cm/individual, and weight 0,28±0,04 g/individual) that had been quarantined and acclimated were stocked into net cages placed at the aforementioned depths, at a density of 100 individuals/m3 or 100 individuals/cage. The cylindrical net cages (0,8 m high, Ø 1 m) were made of 10 mm iron frames and PE nets with a mesh size of 1 mm (inside) and 5 mm (outside). During 126 days of rearing, post-puerulus sand lobster were fed artificial feed once daily at 16:00 – 17:00 WIB, at 15% biomass/day for the first 60 days of rearing and 20% biomass/day from day 61 to day 126 of rearing. Feed was given by diving with the aid of diving and snorkeling equipment. Every 14 days, 30 post-puerulus samples were measured for weight and length to calculate their growth. Hemolymph glucose samples of post-puerulus lobsters were taken on days 0, 63, and 126 of rearing. Water temperature, pH, dissolved oxygen, and salinity at depths of 1, 3, and 6 m were measured in situ daily at 08:00, 12:00, and 16:00 WIB. Water biology, light intensity, and hydrostatic pressure were measured on days 0, 63, and 126 of rearing. The results showed that the water's physico-chemical parameters during the experiment at all three depths were still within the suitable range for sand lobster post-puerulus rearing. As depth increased, dissolved oxygen content decreased, but it remained within the range required for sand lobster post-puerulus survival. Depth affected light intensity and hydrostatic pressure. Seawater at 6 m depth had lower light intensity in the morning, namely 449±230 lux (P<0.05), but did not differ at all depths in the afternoon. Light intensity at 6 m depth (365±180 lux) differed from 1 m (1.116±335 lux) (P<0,05), although there was no difference between 3 and 6 m, nor between 1 and 3 m. The 6 m depth resulted in the highest hydrostatic pressure (P<0,05). The average hydrostatic pressure at 6 m depth was 1,628±0,015 atm. Different depths affected the stress response of sand lobster post-pueruli. The lowest glucose and THC concentrations were found at 6 m depth, at 14,14 mg/100 mL and 1,81 × 104 cells/mm3, respectively (P<0,05). Different depths affected the production performance parameters of sand lobster post-pueruli, namely SR, SR, SGR, AGR, specific length growth rate, absolute length growth rate, total absolute growth length, carapace absolute growth length, frequency of molting, carapace length coefficient of variation, FCR, dan biomassa total (P<0,05). The SR value at 6 m depth was higher (71,00±2,00%) compared to 1 and 3 m depths (41,67±2,08% and 43,67±3,06%). However, the values for SGR, AGR, specific length growth rate, absolute length growth rate, total absolute growth length, carapace absolute growth length, frequency of molting, and carapace length coefficient of variation at 1 and 6 m depths did not differ but differed from 3 m. The FCR value at 6 m depth did not differ from 1 m, but differed at 3 m. The final biomass at 6 m depth had the highest value (526,08±63,52 g) compared to 1 and 3 m. The sand lobster post-puerulus rearing business at 6 m depth yielded higher profits, better break-even points (units and Rp), R/C ratio, and better production costs compared to 1 and 3 m depths. Furthermore, the 6 m depth was financially viable based on financial criteria analysis (NPV, Net B/C, IRR, and PP), while other depths were not viable. Sensitivity analysis was only performed for the 6 m depth, which was deemed investable. A decrease in SR by up to 62,96% or 11,28% was quite sensitive to the sand lobster post-puerulus nursery business. Survival rate affected business profit (P<0,05). Similarly, an increase in puerulus price reaching Rp10,676 per individual (48,63%) was sensitive to the 6 m depth rearing business. An increase in feed price, however, was not sensitive to the 6 m depth rearing business. Rearing sand lobster post-pueruli in net cages at 6 m depth provided the best production performance, was the most profitable, and is feasible for development.