THE ROLE OF MACROBENTHIC COMMUNITIES AS AN INDICATOR FOR THE FERTILITY OF MANGROVE POND: CASE STUDY AT BLANAKAN, SUBANG, WEST JAVA

Macrobenthic in mangrove ecosystems plays an important role as removal particles from the water column to the sediments. Ecology indexes of macrobenthic communities were used in this study as an indicator for the fertility of mangrove pond ecosystems. The study was carried out at mangrove pond in Blanakan, West Java. Data was collected from four sampling sites: opened pond (TB), sylvofishery pond (TS), sedimented pond (TT), and conservation pond (TP). Some ecological indexes such as Margalef’s Index (R), Shannon-Wiener Index (H’), Pielou Evenness Index (E), and Simpson Dominance Index (D) were used to analyze macrobenthic communities. The results showed that infaunal macrobenthic communities were stable at TP with R: 1.91±0.42, H’: 1.59±0.30, E: 0.74±0.14, and D: 0.29±0.12. They were unstable at TB with R: 1.63±0.80, H’: 1.36±0.32, E: 0.74±0.06, and D: 0.35±0.07. The macrobenthic communities can be used as indicator for the fertility of mangrove pond in Blanakan, West Java

Economic Valuation of Mangrove Ecosystem at Gerung District, West Lombok Regency

Research regarding economic valuation of mangrove in Gerung District, West Lombok Regency has been conducted. The purposes of this research were to calculate and analyze economic value from mangrove ecosystem at Gerung District. Research methods used observation and interviews. Direct Economic Value (DEV) were obtained from direct use of mangrove with a value IDR. 227,040,000/year. Indirect Economic Value (IEV)were calculated from mangrove ecosystem services with a value IDR. 1,405,041,200/year, Existence Value (EV) was obtained by Contingent Valuation Method (CVM) with a value IDR. 1,520,000/year. Option Value (OV) were calculated from biodiversity value with a value were IDR. 1,200,000/year. Total Economic Value (TEV) of mangrove in Gerung District were IDR. 1,634,801,200/year

Length-weight relationship and condition factor in giant harpiosquillid Mantis shrimp, Harpiosquilla raphidea (Crustacea: Stomatopoda) in Banten Bay waters, Indonesia

Length-weight relationship of Harpiosquilla raphidea from Banten Bay waters was studied from 146 males and 186 females ranging from 38 to 354 and from 37 to 348 mm, respectively. The following equations were obtained Ln W = 5.164 + 2.478 Ln X (for males), Ln W = 5.333 + 2.596 Ln X (for females) and Ln W = 5.264 + 2.549 Ln X, Ln X (pooled). The ‘b’ values (2.5497) found not near to 3 indicating allometric growth being matched up with the cube law. The ANCOVA indicated not much variation between the ‘b’ values for males and females. In general, the growth rate of the mantis shrimp H. raphidea almost the same or not much different from other mantis shrimp species of the order Stomatopoda

BIOLOGI REPRODUKSI IKAN MADIDIHANG (Thunnus albacares Bonnatere 1788) DI TELUK TOMINI

Penelitian biologi reproduksi bertujuan untuk mengetahui perkembangan gonad dan panjang pertama kali matang gonad ikan madidihang yang tertangkap di perairan Teluk Tomini. Jumlah sampel telur sebanyak 74 contoh dan sampel testes sebanyak 90 contoh dikumpulkan melalui tempat pendaratan ikan di Marisa, Gorontalo pada tahun 2007. Tingkat kematangan gonad diamati secara visual dan pembuatan preparat histologis serta analisis Gonado Somatic Index (GSI). Hasil penelitian ini menunjukkan bahwa pemijahan ikan madidihang diperkirakan terjadi pada bulan Desember dan panjang pertama kali matang gonad pada ukuran 94 cm FL. Nisbah kelamin ikan madidihang jantan dan betina adalah seimbang. The objective of research on reproductive biology of yellowfin tuna is to study  gonad development and its length at first maturity.Gonad development were determined through the examination of 74 yellowfin ovaries samples and 90 testes samples collected from Marisa, Gorontalo in 2007.  Gonad maturity stages were identified histologically. Sexual maturity stages was identified through visual analyzed, preparation on histology and Gonado Somatic Index (GSI). The result showed that spawning season of yellowfin tuna in Tomini Bay occured in December.Meanwhile length at first maturity at 94,8 cm FL. The ratio of males and females of yellowfin tuna is well-balanced

VARIASI UKURAN DAN JENIS MANGSA DARI IKAN MADIDIHANG MUDA (IMMATURE) DAN DEWASA (MATURE)

Penelitian ini bertujuan untuk mengetahui hubungan antara mangsa dan pemangsa (ikan madidihang) di perairan Marisa. Pengambilan contoh dilakukan di Marisa, Provinsi Gorontalo, pada perusahaan fillet ikan tuna. Pengamatan isi lambung dilakukan secara visual. Hasil penelitian menunjukan bahwa tidak terdapat hubungan antara pertambahan ukuran mangsa dengan ukuran ikan pemangsa (madidihang), tapi terdapat hubungan antara jenis mangsa dengan ukuran ikan pemangsa. Ikan madidihang yang berukuran besar (matang gonad) memakan tuna kecil (Auxis rochei) dan ikan pelagis kecil (Brama dussumieri dan Selar crumenopthalmus), sedangkan ikan madidihang yang belum matang gonad banyak memakan Canthigaster spp., Monacanthidae, dan Balistidae. Kanibalisme tidak terjadi di perairan Teluk Tomini. The objective of this research was to study on the relationship between predator and prey for yellowfin tuna in Tomini Bay. Sampling site were located at Marisa, Gorontalo Province in 2007. Prey composition of yellowfin tuna was visually determined. The results showed that there was no relationship between the size of yellowfin tuna and their preys, however, there was indication that different size of yellowfin tuna feed on different item of foods. Adults yellowfin tuna feed little tuna (Auxis rochei) and small pelagic fish Brama dussumieri and Selar cromenopthalmus), while immature yellowfin tuna feed mostly Canthigaster spp., Monacanthidae and Balistidae

SEBARAN DAN HUBUNGAN PARAMETER REPRODUKSI IKAN TUNA MADIDIHANG (Thunnus albacares) DENGAN SUHU DAN KLOROFIL-a DI LAUT BANDA

Laut Banda diketahui mempunyai kondisi lingkungan yangmendukung sebagai daerah pemijahan ikan tuna madidihang (Thunnus albacares). Sebaran parameter reproduksi dan hubungannya dengan lingkungan perlu diketahui sebagai dasar pengelolaan sumberdaya yang lestari. Penelitian dilakukan tahun 2011-2012 dengan basis pendataan di Bandaneira. Pengamatan parameter reproduksi dilakukan terhadap ikan sampel melalui observasi dan enumerasi. Suhu dan klorofil-a diperoleh = dari analisis citra satelit. Penelitian mendapatkan persentase gonad matang (100 %) dan indeks kematangan gonad tertinggi (3,75) serta nisbah kelamin seimbang, secara temporal ditemukan pada bulan antara September-Desember, secara spasial ditemukan di Perairan Gunung Api dan Selatan Kepulauan Lease. Tingkat kematangan gonad dan indeks kematangan gonad meningkat terjadi pada saat suhu mulai menghangat dan klorofil-a mulai menurun. Tingkat kematangan gonad dan indeks kematangan gonad menurun terjadi pada saat awal penurunan suhu dan awal kenaikan klorofil-a.Besides known as the Banda Sea region yellowfin tuna migration (Thunnus albacares) is also a spawning area. Distribution of Reproduction parameter and their relationship with environmental parameter should be known as the basis for sustainable resource management. The reproduction parameter obtaianed by observation and enumeration. Temperature and chlorophyll-a obtained by satellite image analysis. Research gets a high percentage of the gonads mature (100%) and gonad maturity index (3,75) and a balanced sex ratio, temporally be found in the September-December, spatially found in the waters of Pulau Gunung Api and Lease Islands. The maturity level of gonads and gonadal maturation index increases occurred when the temperatures begin to warm and chlorophyll-a start to decline. The maturity level of gonads and gonadal maturation index decreases occurred at the beginning of the early drop in temperature and increase in chlorophyll-a