Cakalang (Katsuwonus pelamis) adalah salah satu hasil tangkapan penting bagi nelayan di Samudera ... more Cakalang (Katsuwonus pelamis) adalah salah satu hasil tangkapan penting bagi nelayan di Samudera Hindia. Penelitian ini bertujuan untuk mengetahui perkembangan gonad dan panjang pertama kalimatang gonad cakalang di Samudera Hindia. Sampel cakalang dikumpulkan dari beberapa tempat di Pantai Selatan Jawa yaitu: Palabuhanratu, Cilacap, Pacitan, Sendang Biru, Kedonganan, Tanjung Luar, Labuhan Lombok dan Oeba dari bulan April 2012 sampai November 2013. Panjang cagak dari 136 sampel berkisar antara 35-68 cm. Tingkat kematangan gonad (TKG) diamati secara histologi dan analisis Gonadosomatic index (GSI). Hasil penelitian ini menunjukkan bahwa TKGcakalang didominasi oleh TKGIV sebesar 43%, diikuti dengan TKG III (21%), TKG I (17%), TKG II (16%) dan TKG V (2%). Panjang pertama kali matang gonad terjadi pada ukuran 42,9 cm. Skipjack tuna (Katsuwonus pelamis) is the one of the important catch for fishermen in the Indian Ocean. The objectives of this research are to investigate gonad maturity an...
Whole otoliths, sectioned otoliths, scales and vertebrae were used to select the most suitable fo... more Whole otoliths, sectioned otoliths, scales and vertebrae were used to select the most suitable for age determination of redfin perch, Percafluviatilis. Redfin perch were sampled from Trevallyn Lake and Brushy Lagoon using fyke nets, gillnets, electrofishing and rod and line angling. Age estimates were assessed for comparison between readings and among structures. One-way ANOVA of readability scores highlighted that sectioned otolith was the most obvious compare to other hard parts. Sectioned otoliths also showed the highest (93.9%) agreement between readings, followed by vertebrae (68.7), scales (38.8) and whole otoliths (29.9). Furthermore, there were no significantly different (p > 0.05) between first and second readings from sectioned otolith and vertebrae but significantly different (p < 0.05) to those from scales and whole otoliths. When sectioned otoliths’ ages were compared with other structures, vertebrae showed the highest (47.6%) agreement to those followed by scales...
IOP Conference Series: Earth and Environmental Science
Mustelus manazo (Starspotted smooth-hound shark) is one of the important catch for small scale fi... more Mustelus manazo (Starspotted smooth-hound shark) is one of the important catch for small scale fisheries in West Nusa Tenggara. This species belongs to the family Triakidae. According to the IUCN Red List, the conservation status of this species is data deficient, which means that there is insufficient information to conduct a proper assessment of conservation status. The objective of this study is to estimate the age, growth and mortality of M. manazo in southern West Nusa Tenggara waters. Length data were collected from January to December 2016 in Tanjung Luar Port, West Nusa Tenggara. Electronic length-frequency analysis (ELEFAN) in R Statistics with package &quot;TropFishR&quot; was used to estimate the population parameter. Length converted catch curve analysis was used to estimate the total mortality. The results showed that von Bertalanffy growth model for male was Lt=122 (1-e (-0.1(t+0.01))), for female was Lt=130 (1-e (-0.18(t+0.02))) and for combined sex was Lt=132 (1-e (-0.1(t+0.01))). Total mortality was estimated at 0.25 year-1. The results from this study represent basic information to support fisheries management of M. manazo in Indonesia.
Madidihang (Thunnus albacares) merupakan spesies yang bermigrasi jauh yang distribusinya di perai... more Madidihang (Thunnus albacares) merupakan spesies yang bermigrasi jauh yang distribusinya di perairan tropis hingga perairan subtropis. Spesies ini ditemukan di Samudra Atlantik, Hindia dan Pasifik. Informasi genetik ikan dengan migrasi jauh seperti tuna penting diketahui untuk kepentingan pemanfaatan secara lestari. Penelitian ini bertujuan untuk memperoleh informasi keragaman genetik dan struktur populasi yang dieksploitasi dan kekerabatan populasi madidihang di perairan Indonesia. Pengumpulan sampel genetik dilakukan di tiga lokasi yaitu di Barat Sumatra, Selatan Bali dan perairan Sulawesi Utara. Metode yang digunakan adalah analisis mikrosatelit yang terdiri dari ekstraksi, purifikasi, amplifikasi polymerase chain reaction (PCR) dan elektroforesis. Hasil analisis terhadap 3 loci DNA mikrosatelit menunjukkan bahwa tingkat kekerabatan ketiga kelompok sampel relatif dekat yaitu berkisar antara 0,132-0,206. Hal ini menunjukkan bahwa Populasi madidihang di perairan Indonesia merupakan...
Albakora (Thunnus alalunga) merupakan salah satu hasil tangkapan ikan ekonomis penting bagi nelay... more Albakora (Thunnus alalunga) merupakan salah satu hasil tangkapan ikan ekonomis penting bagi nelayan rawai tuna di Indonesia. Penelitian ini bertujuan untuk mengetahui pengaruh lama waktu tebar pancing dan perendaman rawai tuna terhadap hasil tangkapan albakora. Pengumpulan data penelitian ini dilakukan oleh observer pada armada rawai tuna yang berfungsi di Samudra Hindia, dilakukan dari bulan Agustus 2005 hingga Agustus 2016. Lama waktu tebar pancing rawai tuna berkisar antara 2-9 jam dengan lama waktu perendaman 1-14 jam atau rata-rata 5 jam. Analisis sidik ragam satu arah menunjukkan bahwa terdapat pengaruh yang nyata pada lama waktu tebar pancing dan perendaman terhadap hasil tangkapan albakora (F9,1020=5,72;…
Tongkol komo (Euthynnus affinis Cantor, 1849) merupakan salah satu hasil tangkapan yang cukup pen... more Tongkol komo (Euthynnus affinis Cantor, 1849) merupakan salah satu hasil tangkapan yang cukup penting bagi perikanan skala kecil di Tanjung Luar, Nusa Tenggara Barat. Spesies ini masuk ke dalam kelompok tuna neritik yang sebagian besar diusahakan dengan menggunakan alat tangkap purse seine dan gillnet. Penelitian ini bertujuan untuk mengetahui pola pertumbuhan dan faktor kondisi tongkol komo. Pengumpulan data dilakukan selama 12 bulan dari Januari – Desember 2016 di PPI Tanjung Luar, Nusa Tenggara Barat. Pengambilan data bulanan secara berkesinambungan dilakukan dengan bantuan tenaga enumerator. Data sebanyak 1.297 spesimen komo telah diukur panjang cagak (cmFL) dan ditimbang beratnya (kg). Hasil pengukuran menunjukkan sebaran panjang berkisar antara 24 – 71 cmFL, dengan rata-rata 51,66 cmFL dan berat 0,21 – 7,05 kg, dengan rata-rata 2,72 kg. Analisis hubungan panjang berat diperoleh hasil W= 0,00001 FL3,114 dengan koefisien determinasi (R2) 0,978. Pola pertumbuhan bersifat alometri...
Relative abundance indices as calculated based on commercial catches are the input data to run st... more Relative abundance indices as calculated based on commercial catches are the input data to run stock assessment models to gather useful information for decision making in fishery management. A Generalized Linear Model (GLM) was used to calculate relative abundance indices and effect of longline fishing gear configuration. Data were collected by a scientific observer program from August 2005 to November 2013. Most of the boats monitored were based in the Benoa Port, Bali. Catches are often equal to zero because swordfish is a bycatch for Indonesian longline fleets. Therefore, a hurdle model and a binomial distribution was used to model the proportion of positive catch rates, while a gamma distribution were used to model the positive longline sets. Correlations between the proportion of positive sets and year () and quarter () were weak. However, linear correlation between the proportion of positive sets and the length of branch lines () and number of hooks between floats () were nega...
Indonesian tuna longline fleets have been fishing in the Exclusive Economic Zone (EEZ) and high s... more Indonesian tuna longline fleets have been fishing in the Exclusive Economic Zone (EEZ) and high seas of the Indian Ocean for quite some time. However, effort has never been made to separate catch from the EEZ and the high seas as it important for fisheries management. A total of 2,430 set-by-set longline fishing data had been collected by scientific observers based in the Research Institute of Tuna Fishery in Bali since August 2005 to December 2014 on which present analysis was made. The research aims to compare between trend of tuna catch of the EEZ and of the high seas of Indian Ocean. The results show that the mean hook rate of both catches of big eye tuna (BET) and southern Bluefin tuna (SBT) caught in the high seas was significantly higher than that the EEZ (two sample t-test, p<0.05), while for yellow fin tuna (YFT) it was in the opposite direction (two sample t-test, p<0.05). As for albacore (ALB), the mean hook rate value was statistically similar in both fishing groun...
Tuna, cakalang dan tongkol (TCT) merupakan jenis hasil tangkapan ikan yang memiliki nilai ekonomi... more Tuna, cakalang dan tongkol (TCT) merupakan jenis hasil tangkapan ikan yang memiliki nilai ekonomis penting dan masih terdapat peluang untuk dimanfaatkan. Salah satu sentra perikanan tuna, cakalang dan tongkol di kawasan Indonesia Barat yang terbesar adalah di Kabupaten Malang tepatnya di Pelabuhan Perikanan Pantai (PPP) Pondokdadap Sendang Biru. Jenis alat penangkapan ikan yang digunakan oleh nelayan untuk menangkap tuna di perairan ini adalah pancing ulur (handline) yang dioperasikan dengan menggunakan bantuan rumpon. Tujuan penelitian ini adalah untuk mengetahui informasi sebaran daerah penangkapan (teritorial, ZEE dan laut lepas) dan bagaimana dinamika hasil tangkapannya khususnya tuna, cakalang dan tongkol. Pancing ulur mendominasi alat penangkapan ikan yang digunakan di PPP Pondokdadap, Sendang Biru tercatat sebanyak 70,42%, sedangkan pukat cincin sebanyak 9,82% dan pancing rawai sebanyak 19,76%. Jenis hasil tangkapan pancing ulur terbanyak adalah cakalang dan juwana tuna. Daer...
Fish aggregating devices, or FADs are used extensively in developing countries to attract and to ... more Fish aggregating devices, or FADs are used extensively in developing countries to attract and to collect pelagic fish and give positive impacts on fish production. Use of FADs has started in early 20th century with different names among the countries and regions. This study investigated the design, deployment, distribution, density and the number of FADs used by small scale tuna fisherman in Labuhan Lombok, including characteristics of fishing boat, fishing gear, catch composition, catch per unit of effort (CPUE), fish diversity and species richness. There were 65 FADs identified in this study and 47 of them were in normal distribution. Type of the FADs used was anchored FADs, spreading between 56.63 to 267.70 NM from Labuhan Lombok fishing port. The placement of FADs were arranged in such a way as to resemble a fence, in which the distance from one to another was close. It is expected to disrupt tuna movement towards the strait in the small islands around West Nusa Tenggara. The di...
Tiger shark is one of the important catch for small scale fisheries in West Nusa Tenggara. It is ... more Tiger shark is one of the important catch for small scale fisheries in West Nusa Tenggara. It is considered nearly threatened according the IUCN, thus information regarding to its estimated population is needed for conservative efforts. This study aimed to estimate the biological and population parameters of the tiger shark in Indonesia. Length data were collected from March to December 2018 in Tanjung Luar Port, West Nusa Tenggara. The length-weight relationship was calculated using equation W=aLb. Electronic length-frequency analysis (ELEFAN) in R Statistics with package “TropFishR” was used to estimate the population parameter. Length converted catch curve (LCCC) analysis was used to estimate the total mortality of the species. The results showed the length-weight relationship for combined sex, male and female was similar to the equation W=0.000001L3.15. The growth pattern for this species was positive allometric which means that the growth of weight is faster than its length. To...
ILMU KELAUTAN: Indonesian Journal of Marine Sciences
The early life of fish larvae is important to understand the entire life history of the fish. At ... more The early life of fish larvae is important to understand the entire life history of the fish. At this phase, larvae movement is very weak and dependent on the movement of water currents. This study aims to determine the distribution and abundance of fish larvae in the waters south of the Port of Tanjung Luar, West Nusa Tenggara, Indonesia. Sampling of fish larvae were done at five stations at waters around Alas Strait and Indian Ocean south of East Lombok. Sampled were collected from 5 different depth: 0-200 m, 201-1000 m, 1001-2000 m, 2001-3000 m and…
Indonesia waters are fertile waters marked by the existence of Regional Fisheries Management (WPP... more Indonesia waters are fertile waters marked by the existence of Regional Fisheries Management (WPP), one of them is WPP 573 in Southern Java. One of the biggest fish catch sectors in Indonesia is tuna fisheries. Distribution of tuna in Indonesia waters affected by Sea Surface Temperature (SST) and chlorophyll-a. The aims of this study is to analyze the distribution of chlorophyll-a and SST in the water of South Java - Bali using AQUA MODIS satellite through data in-situ, to know the accuracy of SST Ground Truth and SST imagery satellite and to find the relationship between chlorophyll-a and SST with catches tuna in the water of South Java - Bali. SST data and chlorophyll-a were obtained through remote sensing technology and the catches of tuna was obtained by in-situ. The methods used were polynomial regression analysis, regression linear analysis and correlation analysis to determine the relationship of these parameters, found strong correlation between SST Ground Truth and SST imag...
ILMU KELAUTAN: Indonesian Journal of Marine Sciences
Skipjack tuna (Katsuwonus pelamis) is highly migratory species that spread from trophic and sub t... more Skipjack tuna (Katsuwonus pelamis) is highly migratory species that spread from trophic and sub trophic waters. This species can be found in Atlantic, Indian and Pacific oceans. The genetic information of highly migratory species like skipjack tuna is important to support the sustainability of the fisheries. The objectives of this study are to gain information genetic diversity and population structure of exploited species and to understand the population kinship in Indonesian waters. Tissue samples were collected from six locations, i.e.: Sibolga (North Sumatera), Padang (West Sumatera), Binuangeun (Banten), Pacitan (East Java), Lombok (West Nusa Tenggara) and Kupang (East Nusa Tenggara). Microsatellite analysis was done in this study consisting of extraction, purification, polymerase chain reaction (PCR) amplification and electrophoresis. Three loci used for the analysis i.e.: UTD 172, UTD 523 and UTD 535. The results showed that there are two groups from six locations i.e.: group...
Marine Fisheries : Journal of Marine Fisheries Technology and Management
This study presents information about the dynamics of industrial scale tuna longline development ... more This study presents information about the dynamics of industrial scale tuna longline development in Indonesia, especially tuna longline fisheries in the Eastern Indian Ocean. This study uses a descriptive method based on tuna longline enumeration data landed at Benoa port from 2012 to 2015. Benoa is one of the three main fishing ports in Indonesia, besides Nizam Zachman (Jakarta) and Cilacap (Central Java). It contributes the largest number of tuna catches to 60% of the total long-scale tuna catch industry in the Indian Ocean. This makes Benoa as the main barometer of industrial tuna fisheries in Indonesia. Industrial scale of tuna longline fisheries activities have dropped significantly to 76% from 2004 to 2015. Highest decline occurred in 2004 to 2006 by 43% followed by 2009 to 2010 at 41% and 2014 to 2015 at 19%. Enumeration data coverage in Benoa port is about 57% to 64% of total ship landing. Catch dominated by export products followed by local quality and bycatch products. The catch composition is dominated by four tuna species (BET, YFT, SBT and ALB) which reach 88% of the total catch followed by bycatch of 6.23% and fish with beaks of 5.46%. In period 2012 to 2014, fishing efforts are directly proportional to the number of ships and tuna production, but in 2015, capture efforts, CPUE and catch production increased along with the decline in the number of ships operating.
Kawakawa (Euthynnus affinis) is one of the economically important fish species for fishermen in D... more Kawakawa (Euthynnus affinis) is one of the economically important fish species for fishermen in Denpasar, Bali. The objective of this study was to analyze the reproductive biology of kawakawa such as the gonadal maturity level (GML), gonad maturity index (GMI) and the length proportion of the mature gonads 50% (L50) and 95% (L95) of kawakawa in the Eastern Indian Ocean. Fish samples were collected from the fishermen catch landed at Kedonganan Fishing Port (PPI), Bali from May to September 2016. The total of fish samples collected were 168 individual. Each individual species was measured their fork length (FL), individual weight, gonad weight and determination of gonadal maturity level. The data obtained were analyzed to determine GML, GMI and proportions of gonads mature. The results showed that the fork length ranged from 26-55 cm with an average of 38 cm and dominated by a 28 cm. The maturity level of fish gonads was dominated by GML III (38%), followed by GML II (26%), GML I (22%...
Yellowfin tuna, Thunnus albacares (Bonnaterre, 1788) is one of the important economically for tun... more Yellowfin tuna, Thunnus albacares (Bonnaterre, 1788) is one of the important economically for tuna species that spread in Indonesian waters, including in WPP 572 (Indian Ocean west coast of Sumatra). One important aspect relating to sustainable utilization is the growth pattern and the condition factor. This study aims to examine growth patterns and factor conditions of yellowfin tuna in the Eastern Indian Ocean. The number of fish samples measured in length and weight is 7,550 with length range from 76-176 cm (average: 129.03 cm) and mode at 150 cm. The length weight relationship of the species is W=4x10-5L2.842 (R2 0,957). In general the growth pattern of yellowfin tuna is negative allometric which means that the length increase is faster than the weight. The average relative condition factor of yellowfin tuna is 0.975 with a tendency to decrease along with the increasing of its length. The highest relative condition factor occurred at the length class of 80 cm with 1,061 and the ...
Madidihang (Thunnus albacares)adalah salah satu hasil tangkapan penting bagi nelayan di Samudra H... more Madidihang (Thunnus albacares)adalah salah satu hasil tangkapan penting bagi nelayan di Samudra Hindia.Penelitian inibertujuan untuk mengetahui aspek biologi reproduksi madidihang yaitu: tingkat kematangan gonad, dugaan musim pemijahan dan panjang pertama kali matang gonad (Lm).Penelitian ini dilaksanakan dari bulan Februari hingga November 2016 dengan dengan mengambil sampel gonad di beberapa tempat pendaratan ikan yaitu: Padang, Palabuhanratu, Cilacap, Kedonganan, Benoa, Tanjung Luar dan Kupang. Sebanyak191 ekor madidihang dikumpulkan dengan sebaran panjang cagak 54-162 cm dan rata-rata panjang cagak 131 cm.Tingkat kematangan gonad (TKG) madidihang yang tertangkap didominasi oleh TKG IV sebesar 50%, diikuti oleh TKG I (31%), TKG III (9%), TKG II (7%) dan TKG V (3%). Rata-rata Gonadosomatic index (GSI) madidihang adalah 1,03 (0,11-7,81). Sebaran GSI tiap bulan menunjukkan bahwa GSI tertinggi terjadi pada bulan November sebesar 1,32 sedangkan terendah terjadi pada bulan Juni sebesar...
Turtle is one of the vulnerable of megafauna and as a by-catch in tuna longline fisheries however... more Turtle is one of the vulnerable of megafauna and as a by-catch in tuna longline fisheries however management practices have not been done yet. This paper described the efforts to avoid the capture of turtles on the tuna longline fishery and its handling recommendation. It has been written based on the research results and observer programs of activities that have been implemented since 2005. It's also including a literature review rules and regulations regarding the management of sea turtles. The record results during 2005-2014 conducted by independent scientific board on tuna longline in the Indian Ocean with 72 times number of setting and 89,441number of hooks. There are 105 turtles caught, which are leatherback, olive ridley turtles, hawksbill, loggerhead sea turtles as well as the unknown green turtle where the current status of turtles in the Indian Ocean is in a state of vulnerable, endangered, critically even endangered. The olive ridley turtle, loggerhead and leatherback turtles are in a vulnerable status. While green turtles are in a state endangered and even hawksbill in a state extremely endangered. Policy measures for handling of turtles in tuna longline fishery needs to be taken in order to be implemented include the socialization of the use of intensified circle hooks and if necessary the government issued regulations regarding the use of circle hooks, the implementation of the placement of fishing monitoring (observer) aboard the tuna longline in order to assist the skippers monitoring the catch of turtles and turtle handling training for the skippers and crew in order to hold the caught turtles can be handled directly on the boat to reduce the mortality turtles which can be released back into the sea alive.
Tongkol komo (Euthynnus affinis Cantor, 1849)merupakan hasil tangkapan utama bagi nelayan pukat c... more Tongkol komo (Euthynnus affinis Cantor, 1849)merupakan hasil tangkapan utama bagi nelayan pukat cincin di Samudera Hindia sebelah barat Sumatera. Penelitian ditujukan untukmemperoleh data dan informasi tentang estimasi laju pertumbuhan, laju kematian dan laju eksploitasi ikan tongkol komo. Analisis dilakukan berdasarkan himpunan data frekuensi panjang cagak sebanyak 1.325 ekor hasil tangkapan pukat cincin yang didaratkan di Pelabuhan Sibolga. Contoh ikan dikumpulkan secara bulanan dari bulan Juli 2012 hingga Februari 2013. Pendugaan parameter dilakukan menggunakan program FISAT II (FAO-ICLARM Stock Assessment Tools). Hasil kajian menunjukkan kisaran panjang cagak antara 30 - 60 cm, panjang asimptotik (L∞)= 63,5 cm, laju pertumbuhan(K) = 0,63/tahun dan umur teoritis pada saat panjang ke 0 ( t0 ) = -0,21 tahun. Estimasi laju kematian total tahunan (Z) sebesar 2,40/tahun, laju kematian alami (M) sebesar 1,07/tahun dan laju kematian akibat penangkapan(F) sebesar 1,33/tahun. Perkiraan La...
Cakalang (Katsuwonus pelamis) adalah salah satu hasil tangkapan penting bagi nelayan di Samudera ... more Cakalang (Katsuwonus pelamis) adalah salah satu hasil tangkapan penting bagi nelayan di Samudera Hindia. Penelitian ini bertujuan untuk mengetahui perkembangan gonad dan panjang pertama kalimatang gonad cakalang di Samudera Hindia. Sampel cakalang dikumpulkan dari beberapa tempat di Pantai Selatan Jawa yaitu: Palabuhanratu, Cilacap, Pacitan, Sendang Biru, Kedonganan, Tanjung Luar, Labuhan Lombok dan Oeba dari bulan April 2012 sampai November 2013. Panjang cagak dari 136 sampel berkisar antara 35-68 cm. Tingkat kematangan gonad (TKG) diamati secara histologi dan analisis Gonadosomatic index (GSI). Hasil penelitian ini menunjukkan bahwa TKGcakalang didominasi oleh TKGIV sebesar 43%, diikuti dengan TKG III (21%), TKG I (17%), TKG II (16%) dan TKG V (2%). Panjang pertama kali matang gonad terjadi pada ukuran 42,9 cm. Skipjack tuna (Katsuwonus pelamis) is the one of the important catch for fishermen in the Indian Ocean. The objectives of this research are to investigate gonad maturity an...
Whole otoliths, sectioned otoliths, scales and vertebrae were used to select the most suitable fo... more Whole otoliths, sectioned otoliths, scales and vertebrae were used to select the most suitable for age determination of redfin perch, Percafluviatilis. Redfin perch were sampled from Trevallyn Lake and Brushy Lagoon using fyke nets, gillnets, electrofishing and rod and line angling. Age estimates were assessed for comparison between readings and among structures. One-way ANOVA of readability scores highlighted that sectioned otolith was the most obvious compare to other hard parts. Sectioned otoliths also showed the highest (93.9%) agreement between readings, followed by vertebrae (68.7), scales (38.8) and whole otoliths (29.9). Furthermore, there were no significantly different (p > 0.05) between first and second readings from sectioned otolith and vertebrae but significantly different (p < 0.05) to those from scales and whole otoliths. When sectioned otoliths’ ages were compared with other structures, vertebrae showed the highest (47.6%) agreement to those followed by scales...
IOP Conference Series: Earth and Environmental Science
Mustelus manazo (Starspotted smooth-hound shark) is one of the important catch for small scale fi... more Mustelus manazo (Starspotted smooth-hound shark) is one of the important catch for small scale fisheries in West Nusa Tenggara. This species belongs to the family Triakidae. According to the IUCN Red List, the conservation status of this species is data deficient, which means that there is insufficient information to conduct a proper assessment of conservation status. The objective of this study is to estimate the age, growth and mortality of M. manazo in southern West Nusa Tenggara waters. Length data were collected from January to December 2016 in Tanjung Luar Port, West Nusa Tenggara. Electronic length-frequency analysis (ELEFAN) in R Statistics with package &quot;TropFishR&quot; was used to estimate the population parameter. Length converted catch curve analysis was used to estimate the total mortality. The results showed that von Bertalanffy growth model for male was Lt=122 (1-e (-0.1(t+0.01))), for female was Lt=130 (1-e (-0.18(t+0.02))) and for combined sex was Lt=132 (1-e (-0.1(t+0.01))). Total mortality was estimated at 0.25 year-1. The results from this study represent basic information to support fisheries management of M. manazo in Indonesia.
Madidihang (Thunnus albacares) merupakan spesies yang bermigrasi jauh yang distribusinya di perai... more Madidihang (Thunnus albacares) merupakan spesies yang bermigrasi jauh yang distribusinya di perairan tropis hingga perairan subtropis. Spesies ini ditemukan di Samudra Atlantik, Hindia dan Pasifik. Informasi genetik ikan dengan migrasi jauh seperti tuna penting diketahui untuk kepentingan pemanfaatan secara lestari. Penelitian ini bertujuan untuk memperoleh informasi keragaman genetik dan struktur populasi yang dieksploitasi dan kekerabatan populasi madidihang di perairan Indonesia. Pengumpulan sampel genetik dilakukan di tiga lokasi yaitu di Barat Sumatra, Selatan Bali dan perairan Sulawesi Utara. Metode yang digunakan adalah analisis mikrosatelit yang terdiri dari ekstraksi, purifikasi, amplifikasi polymerase chain reaction (PCR) dan elektroforesis. Hasil analisis terhadap 3 loci DNA mikrosatelit menunjukkan bahwa tingkat kekerabatan ketiga kelompok sampel relatif dekat yaitu berkisar antara 0,132-0,206. Hal ini menunjukkan bahwa Populasi madidihang di perairan Indonesia merupakan...
Albakora (Thunnus alalunga) merupakan salah satu hasil tangkapan ikan ekonomis penting bagi nelay... more Albakora (Thunnus alalunga) merupakan salah satu hasil tangkapan ikan ekonomis penting bagi nelayan rawai tuna di Indonesia. Penelitian ini bertujuan untuk mengetahui pengaruh lama waktu tebar pancing dan perendaman rawai tuna terhadap hasil tangkapan albakora. Pengumpulan data penelitian ini dilakukan oleh observer pada armada rawai tuna yang berfungsi di Samudra Hindia, dilakukan dari bulan Agustus 2005 hingga Agustus 2016. Lama waktu tebar pancing rawai tuna berkisar antara 2-9 jam dengan lama waktu perendaman 1-14 jam atau rata-rata 5 jam. Analisis sidik ragam satu arah menunjukkan bahwa terdapat pengaruh yang nyata pada lama waktu tebar pancing dan perendaman terhadap hasil tangkapan albakora (F9,1020=5,72;…
Tongkol komo (Euthynnus affinis Cantor, 1849) merupakan salah satu hasil tangkapan yang cukup pen... more Tongkol komo (Euthynnus affinis Cantor, 1849) merupakan salah satu hasil tangkapan yang cukup penting bagi perikanan skala kecil di Tanjung Luar, Nusa Tenggara Barat. Spesies ini masuk ke dalam kelompok tuna neritik yang sebagian besar diusahakan dengan menggunakan alat tangkap purse seine dan gillnet. Penelitian ini bertujuan untuk mengetahui pola pertumbuhan dan faktor kondisi tongkol komo. Pengumpulan data dilakukan selama 12 bulan dari Januari – Desember 2016 di PPI Tanjung Luar, Nusa Tenggara Barat. Pengambilan data bulanan secara berkesinambungan dilakukan dengan bantuan tenaga enumerator. Data sebanyak 1.297 spesimen komo telah diukur panjang cagak (cmFL) dan ditimbang beratnya (kg). Hasil pengukuran menunjukkan sebaran panjang berkisar antara 24 – 71 cmFL, dengan rata-rata 51,66 cmFL dan berat 0,21 – 7,05 kg, dengan rata-rata 2,72 kg. Analisis hubungan panjang berat diperoleh hasil W= 0,00001 FL3,114 dengan koefisien determinasi (R2) 0,978. Pola pertumbuhan bersifat alometri...
Relative abundance indices as calculated based on commercial catches are the input data to run st... more Relative abundance indices as calculated based on commercial catches are the input data to run stock assessment models to gather useful information for decision making in fishery management. A Generalized Linear Model (GLM) was used to calculate relative abundance indices and effect of longline fishing gear configuration. Data were collected by a scientific observer program from August 2005 to November 2013. Most of the boats monitored were based in the Benoa Port, Bali. Catches are often equal to zero because swordfish is a bycatch for Indonesian longline fleets. Therefore, a hurdle model and a binomial distribution was used to model the proportion of positive catch rates, while a gamma distribution were used to model the positive longline sets. Correlations between the proportion of positive sets and year () and quarter () were weak. However, linear correlation between the proportion of positive sets and the length of branch lines () and number of hooks between floats () were nega...
Indonesian tuna longline fleets have been fishing in the Exclusive Economic Zone (EEZ) and high s... more Indonesian tuna longline fleets have been fishing in the Exclusive Economic Zone (EEZ) and high seas of the Indian Ocean for quite some time. However, effort has never been made to separate catch from the EEZ and the high seas as it important for fisheries management. A total of 2,430 set-by-set longline fishing data had been collected by scientific observers based in the Research Institute of Tuna Fishery in Bali since August 2005 to December 2014 on which present analysis was made. The research aims to compare between trend of tuna catch of the EEZ and of the high seas of Indian Ocean. The results show that the mean hook rate of both catches of big eye tuna (BET) and southern Bluefin tuna (SBT) caught in the high seas was significantly higher than that the EEZ (two sample t-test, p<0.05), while for yellow fin tuna (YFT) it was in the opposite direction (two sample t-test, p<0.05). As for albacore (ALB), the mean hook rate value was statistically similar in both fishing groun...
Tuna, cakalang dan tongkol (TCT) merupakan jenis hasil tangkapan ikan yang memiliki nilai ekonomi... more Tuna, cakalang dan tongkol (TCT) merupakan jenis hasil tangkapan ikan yang memiliki nilai ekonomis penting dan masih terdapat peluang untuk dimanfaatkan. Salah satu sentra perikanan tuna, cakalang dan tongkol di kawasan Indonesia Barat yang terbesar adalah di Kabupaten Malang tepatnya di Pelabuhan Perikanan Pantai (PPP) Pondokdadap Sendang Biru. Jenis alat penangkapan ikan yang digunakan oleh nelayan untuk menangkap tuna di perairan ini adalah pancing ulur (handline) yang dioperasikan dengan menggunakan bantuan rumpon. Tujuan penelitian ini adalah untuk mengetahui informasi sebaran daerah penangkapan (teritorial, ZEE dan laut lepas) dan bagaimana dinamika hasil tangkapannya khususnya tuna, cakalang dan tongkol. Pancing ulur mendominasi alat penangkapan ikan yang digunakan di PPP Pondokdadap, Sendang Biru tercatat sebanyak 70,42%, sedangkan pukat cincin sebanyak 9,82% dan pancing rawai sebanyak 19,76%. Jenis hasil tangkapan pancing ulur terbanyak adalah cakalang dan juwana tuna. Daer...
Fish aggregating devices, or FADs are used extensively in developing countries to attract and to ... more Fish aggregating devices, or FADs are used extensively in developing countries to attract and to collect pelagic fish and give positive impacts on fish production. Use of FADs has started in early 20th century with different names among the countries and regions. This study investigated the design, deployment, distribution, density and the number of FADs used by small scale tuna fisherman in Labuhan Lombok, including characteristics of fishing boat, fishing gear, catch composition, catch per unit of effort (CPUE), fish diversity and species richness. There were 65 FADs identified in this study and 47 of them were in normal distribution. Type of the FADs used was anchored FADs, spreading between 56.63 to 267.70 NM from Labuhan Lombok fishing port. The placement of FADs were arranged in such a way as to resemble a fence, in which the distance from one to another was close. It is expected to disrupt tuna movement towards the strait in the small islands around West Nusa Tenggara. The di...
Tiger shark is one of the important catch for small scale fisheries in West Nusa Tenggara. It is ... more Tiger shark is one of the important catch for small scale fisheries in West Nusa Tenggara. It is considered nearly threatened according the IUCN, thus information regarding to its estimated population is needed for conservative efforts. This study aimed to estimate the biological and population parameters of the tiger shark in Indonesia. Length data were collected from March to December 2018 in Tanjung Luar Port, West Nusa Tenggara. The length-weight relationship was calculated using equation W=aLb. Electronic length-frequency analysis (ELEFAN) in R Statistics with package “TropFishR” was used to estimate the population parameter. Length converted catch curve (LCCC) analysis was used to estimate the total mortality of the species. The results showed the length-weight relationship for combined sex, male and female was similar to the equation W=0.000001L3.15. The growth pattern for this species was positive allometric which means that the growth of weight is faster than its length. To...
ILMU KELAUTAN: Indonesian Journal of Marine Sciences
The early life of fish larvae is important to understand the entire life history of the fish. At ... more The early life of fish larvae is important to understand the entire life history of the fish. At this phase, larvae movement is very weak and dependent on the movement of water currents. This study aims to determine the distribution and abundance of fish larvae in the waters south of the Port of Tanjung Luar, West Nusa Tenggara, Indonesia. Sampling of fish larvae were done at five stations at waters around Alas Strait and Indian Ocean south of East Lombok. Sampled were collected from 5 different depth: 0-200 m, 201-1000 m, 1001-2000 m, 2001-3000 m and…
Indonesia waters are fertile waters marked by the existence of Regional Fisheries Management (WPP... more Indonesia waters are fertile waters marked by the existence of Regional Fisheries Management (WPP), one of them is WPP 573 in Southern Java. One of the biggest fish catch sectors in Indonesia is tuna fisheries. Distribution of tuna in Indonesia waters affected by Sea Surface Temperature (SST) and chlorophyll-a. The aims of this study is to analyze the distribution of chlorophyll-a and SST in the water of South Java - Bali using AQUA MODIS satellite through data in-situ, to know the accuracy of SST Ground Truth and SST imagery satellite and to find the relationship between chlorophyll-a and SST with catches tuna in the water of South Java - Bali. SST data and chlorophyll-a were obtained through remote sensing technology and the catches of tuna was obtained by in-situ. The methods used were polynomial regression analysis, regression linear analysis and correlation analysis to determine the relationship of these parameters, found strong correlation between SST Ground Truth and SST imag...
ILMU KELAUTAN: Indonesian Journal of Marine Sciences
Skipjack tuna (Katsuwonus pelamis) is highly migratory species that spread from trophic and sub t... more Skipjack tuna (Katsuwonus pelamis) is highly migratory species that spread from trophic and sub trophic waters. This species can be found in Atlantic, Indian and Pacific oceans. The genetic information of highly migratory species like skipjack tuna is important to support the sustainability of the fisheries. The objectives of this study are to gain information genetic diversity and population structure of exploited species and to understand the population kinship in Indonesian waters. Tissue samples were collected from six locations, i.e.: Sibolga (North Sumatera), Padang (West Sumatera), Binuangeun (Banten), Pacitan (East Java), Lombok (West Nusa Tenggara) and Kupang (East Nusa Tenggara). Microsatellite analysis was done in this study consisting of extraction, purification, polymerase chain reaction (PCR) amplification and electrophoresis. Three loci used for the analysis i.e.: UTD 172, UTD 523 and UTD 535. The results showed that there are two groups from six locations i.e.: group...
Marine Fisheries : Journal of Marine Fisheries Technology and Management
This study presents information about the dynamics of industrial scale tuna longline development ... more This study presents information about the dynamics of industrial scale tuna longline development in Indonesia, especially tuna longline fisheries in the Eastern Indian Ocean. This study uses a descriptive method based on tuna longline enumeration data landed at Benoa port from 2012 to 2015. Benoa is one of the three main fishing ports in Indonesia, besides Nizam Zachman (Jakarta) and Cilacap (Central Java). It contributes the largest number of tuna catches to 60% of the total long-scale tuna catch industry in the Indian Ocean. This makes Benoa as the main barometer of industrial tuna fisheries in Indonesia. Industrial scale of tuna longline fisheries activities have dropped significantly to 76% from 2004 to 2015. Highest decline occurred in 2004 to 2006 by 43% followed by 2009 to 2010 at 41% and 2014 to 2015 at 19%. Enumeration data coverage in Benoa port is about 57% to 64% of total ship landing. Catch dominated by export products followed by local quality and bycatch products. The catch composition is dominated by four tuna species (BET, YFT, SBT and ALB) which reach 88% of the total catch followed by bycatch of 6.23% and fish with beaks of 5.46%. In period 2012 to 2014, fishing efforts are directly proportional to the number of ships and tuna production, but in 2015, capture efforts, CPUE and catch production increased along with the decline in the number of ships operating.
Kawakawa (Euthynnus affinis) is one of the economically important fish species for fishermen in D... more Kawakawa (Euthynnus affinis) is one of the economically important fish species for fishermen in Denpasar, Bali. The objective of this study was to analyze the reproductive biology of kawakawa such as the gonadal maturity level (GML), gonad maturity index (GMI) and the length proportion of the mature gonads 50% (L50) and 95% (L95) of kawakawa in the Eastern Indian Ocean. Fish samples were collected from the fishermen catch landed at Kedonganan Fishing Port (PPI), Bali from May to September 2016. The total of fish samples collected were 168 individual. Each individual species was measured their fork length (FL), individual weight, gonad weight and determination of gonadal maturity level. The data obtained were analyzed to determine GML, GMI and proportions of gonads mature. The results showed that the fork length ranged from 26-55 cm with an average of 38 cm and dominated by a 28 cm. The maturity level of fish gonads was dominated by GML III (38%), followed by GML II (26%), GML I (22%...
Yellowfin tuna, Thunnus albacares (Bonnaterre, 1788) is one of the important economically for tun... more Yellowfin tuna, Thunnus albacares (Bonnaterre, 1788) is one of the important economically for tuna species that spread in Indonesian waters, including in WPP 572 (Indian Ocean west coast of Sumatra). One important aspect relating to sustainable utilization is the growth pattern and the condition factor. This study aims to examine growth patterns and factor conditions of yellowfin tuna in the Eastern Indian Ocean. The number of fish samples measured in length and weight is 7,550 with length range from 76-176 cm (average: 129.03 cm) and mode at 150 cm. The length weight relationship of the species is W=4x10-5L2.842 (R2 0,957). In general the growth pattern of yellowfin tuna is negative allometric which means that the length increase is faster than the weight. The average relative condition factor of yellowfin tuna is 0.975 with a tendency to decrease along with the increasing of its length. The highest relative condition factor occurred at the length class of 80 cm with 1,061 and the ...
Madidihang (Thunnus albacares)adalah salah satu hasil tangkapan penting bagi nelayan di Samudra H... more Madidihang (Thunnus albacares)adalah salah satu hasil tangkapan penting bagi nelayan di Samudra Hindia.Penelitian inibertujuan untuk mengetahui aspek biologi reproduksi madidihang yaitu: tingkat kematangan gonad, dugaan musim pemijahan dan panjang pertama kali matang gonad (Lm).Penelitian ini dilaksanakan dari bulan Februari hingga November 2016 dengan dengan mengambil sampel gonad di beberapa tempat pendaratan ikan yaitu: Padang, Palabuhanratu, Cilacap, Kedonganan, Benoa, Tanjung Luar dan Kupang. Sebanyak191 ekor madidihang dikumpulkan dengan sebaran panjang cagak 54-162 cm dan rata-rata panjang cagak 131 cm.Tingkat kematangan gonad (TKG) madidihang yang tertangkap didominasi oleh TKG IV sebesar 50%, diikuti oleh TKG I (31%), TKG III (9%), TKG II (7%) dan TKG V (3%). Rata-rata Gonadosomatic index (GSI) madidihang adalah 1,03 (0,11-7,81). Sebaran GSI tiap bulan menunjukkan bahwa GSI tertinggi terjadi pada bulan November sebesar 1,32 sedangkan terendah terjadi pada bulan Juni sebesar...
Turtle is one of the vulnerable of megafauna and as a by-catch in tuna longline fisheries however... more Turtle is one of the vulnerable of megafauna and as a by-catch in tuna longline fisheries however management practices have not been done yet. This paper described the efforts to avoid the capture of turtles on the tuna longline fishery and its handling recommendation. It has been written based on the research results and observer programs of activities that have been implemented since 2005. It's also including a literature review rules and regulations regarding the management of sea turtles. The record results during 2005-2014 conducted by independent scientific board on tuna longline in the Indian Ocean with 72 times number of setting and 89,441number of hooks. There are 105 turtles caught, which are leatherback, olive ridley turtles, hawksbill, loggerhead sea turtles as well as the unknown green turtle where the current status of turtles in the Indian Ocean is in a state of vulnerable, endangered, critically even endangered. The olive ridley turtle, loggerhead and leatherback turtles are in a vulnerable status. While green turtles are in a state endangered and even hawksbill in a state extremely endangered. Policy measures for handling of turtles in tuna longline fishery needs to be taken in order to be implemented include the socialization of the use of intensified circle hooks and if necessary the government issued regulations regarding the use of circle hooks, the implementation of the placement of fishing monitoring (observer) aboard the tuna longline in order to assist the skippers monitoring the catch of turtles and turtle handling training for the skippers and crew in order to hold the caught turtles can be handled directly on the boat to reduce the mortality turtles which can be released back into the sea alive.
Tongkol komo (Euthynnus affinis Cantor, 1849)merupakan hasil tangkapan utama bagi nelayan pukat c... more Tongkol komo (Euthynnus affinis Cantor, 1849)merupakan hasil tangkapan utama bagi nelayan pukat cincin di Samudera Hindia sebelah barat Sumatera. Penelitian ditujukan untukmemperoleh data dan informasi tentang estimasi laju pertumbuhan, laju kematian dan laju eksploitasi ikan tongkol komo. Analisis dilakukan berdasarkan himpunan data frekuensi panjang cagak sebanyak 1.325 ekor hasil tangkapan pukat cincin yang didaratkan di Pelabuhan Sibolga. Contoh ikan dikumpulkan secara bulanan dari bulan Juli 2012 hingga Februari 2013. Pendugaan parameter dilakukan menggunakan program FISAT II (FAO-ICLARM Stock Assessment Tools). Hasil kajian menunjukkan kisaran panjang cagak antara 30 - 60 cm, panjang asimptotik (L∞)= 63,5 cm, laju pertumbuhan(K) = 0,63/tahun dan umur teoritis pada saat panjang ke 0 ( t0 ) = -0,21 tahun. Estimasi laju kematian total tahunan (Z) sebesar 2,40/tahun, laju kematian alami (M) sebesar 1,07/tahun dan laju kematian akibat penangkapan(F) sebesar 1,33/tahun. Perkiraan La...
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