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Seagrass ecology contributes to the preservation of fish and other biota diversity and is also an important livelihood source for fishermen and local communities. The purpose of our research was (1) to determine the source of the threats toseagrass ecology and to the ecological services it provides for the sustainability of fish resources and (2) to determine the main indicators defining the conservation needs of seagrass in the study area. Data were collected through direct observation, questionnaires, interviews and discussions. Data for fish in the seagrass bed research sites were obtained using mini-trawlers belonging to local fishermen. All data were analyzed using descriptive statistical analyses. The results showed that seagrass beds play an important role in fish ecology and that local livelihoods were highly dependent on small-scale fishing. However, fishermen and local communities also constituted the two main threats to the preservation and sustainability of fish and other biota in the area. Our results found, too, that there is a scarcity of some types of biota: some fish species, mollusks, crabs, see-urchin and some types of sea cucumber were very difficult to find in the seagrass beds that were the focus of our study. Our conclusion is that, given the scarcity of fifteen species of fish, as well as of other biota and the lack of diversity in fish food in our study area, it is imperative that seagrass conservation becomes an important priority for conservation interventions.

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Pada dasarnya pengelolaan perikanan tangkap bertujuan untuk mewujudkan usaha perikanan tangkap yang berkelanjutan. Untuk itu, laju penangkapan ikan harus tidak melebihi potensi produksi lestari (Maximum SustainbleYield, MSY) dari sumber daya ikan dalam suatu wilayah perairan. Namun, pengelola perikanan di Indonesia umumnya berpandangan, bahwa menentukan MSY dan hasil tangkapan ikan di laut susah dan mahal. Dengan metode Surplus Production Model, penelitian ini dimaksudkan untuk mengetahui status pemanfaatan sumber daya ikan berdasarkan pada jenis alat tangkap, zona penangkapan ikan, dan jenis ikan secara lebih mudah dan murah di wilayah perairan laut Kabupaten Cirebon. Penelitian dilakukan dari Oktober 2010 sampai Maret 2011. Hasil penelitian menunjukkan, bahwa status pemanfaatan sumber daya ikan baik di Zona-I, Zona- II maupun Zona-III perairan laut Cirebon pada umumnya telah mengalami gejala tangkap lebih (overfishing). Dari 13 jenis alat tangkap yang digunakan oleh nelayan di daerah penelitian, tujuh diantaranya yakni payang, dogol, pukat arad, jaring insang hanyut, jaring insang lingkar, bagan tancap, dan rawai tetap statusnya sudah melebihi dari jumlah upaya optimum (fopt). Sedangkan, enam jenis alat tangkap lainnya, yaitu pukat tarik, jaring insang tetap, jaring kantong, anco, perangkap kerang, dan perangkap lainnya statusnya masih kurang. Adapun jenis-jenis ikan yang telah mengalami overfishing adalah: teri, teri nasi, bawal hitam, sunglir, gurita, biji nangka, kapas-kapas, slanget, sotong, kurisi, kuniran, peperek, kurau, ikan sebelah, cumi-cumi, manyung, tetengkek, bawal putih, talang, kakap, tongkol, tenggiri, cucut, japuh, tembang, julung-julung, siro, bilis, pari, alu-alu, dan remang.Management of capture fisheries is basically intended to achieve economic activities of capture fisheries on a sustainable basis. Accordingly, the exploitation rate of fisheries resources should not exceed its MSY (Maximum Sustainable Yield) in a marine area. Unfortunately, majority of fisheries management authorities in Indonesia perceive that determining MSY and total fish catch in marine waters is both difficult and expensive. By employing Surplus Production Model, this research aims at evaluating the state of fisheries resource utilization based upon the types of fishing gears, fishing zones, and types of fish stocks in Cirebon marine waters, which is easier and less expensive than it is currently perceived by those management authorities. The results of this research demonstrate that the state of fisheries resources in Zone-I, Zone-II, and Zone-III of Cirebon marine waters has generally been overfishing. Furthermore, among 13 types of fishing gears used in Cirebon marine waters, seven fishing gears are already exceeding the optimum fishing effort (fopt). These include mini purse seine, danish seine, fish net, gill nets, encirling gill nets, fixed lift net, and long lines. Meanwhile, the other six fishing gears including active purse seine, fixed gill nets, trammel nets, anco, trap for molluscs, and other trap types are still less than their optimum number. Amongst so many fish species caught from Cirebon marine waters, thirty one specieas are already overfishing, which include teri, teri nasi, bawal hitam, sunglir, gurita, biji nangka, kapas-kapas, slanget, sotong, kurisi, kuniran, peperek, kurau, ikan sebelah, cumicumi, manyung, tetengkek, bawal putih, talang, kakap, tongkol, tenggiri, cucut, japuh, tembang, julung-julung, siro, bilis, pari, alu-alu, dan remang.

The bilih fish Mystacoleucus padangensis did a migration of the lake to the river that empties into the lake to spawn. This study aimed to determine whether migratory fish bilih ate when and what kind of natural foods consumed by bilih fish in it migration habitat. The study was conducted in Naborsahan River, Toba lake, North Sumatra. Sampling was done every 1 hour using Cast net. The results showed that bilih fish keep doing the feeding activity and having diurnal when migrated. The natural food bilih fish in the river and Toba lake was same, it was the phytoplankton of the class Bacilariopiceae. Natural food bilih fish that found in it intestine were phytoplankton include Rhizosolenia, Synedra, Gonatozygon, Closterium, Surirella, Pinnularia, Oscillatroria, Melosira, Gyrosigma, Aulacoseira and Zooplankton among others Creseis, Tubifex and Daphnia. The type of natural food  that  nostly found  in bilih fish intestines were phytoplankton from the genus Synedra Bacilariopiceae with Index of Preporedance (IP) is 97.9 %. Based on the composition of the natural food that was dominated, bilih fish was categorized as the plankton feeder.

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ABSTRAKIkan bilih (Mystacoleucus padangensis) merupakan salah satu ikan dari famili cyprinidae yang melakukan ruaya pemijahan dari danau menuju sungai. Habitat pemijahan dan asuhan ikan bilih perlu dikaji sebelum melakukan upaya pemulihan kembali ikan bilih di Danau Toba. Tujuan penelitian ini adalah untuk mengetahui habitat pemijahan dan habitat asuhan ikan bilih. Habitat pemijahan ditentukan berdasarkan jumlah ikan matang gonad dan habitat asuhan diidentifikasi berdasarkan keberadaan juvenil ikan bilih di Sungai Naborsahan, Danau Toba Sumatera Utara. Pengambilan sampel ikan bulanan (April 2013 sampai Mei 2014) dilakukan di enam stasiun yang ditentukan berdasarkan karakteristik sungai dan habitat ikan bilih. Ikan bilih matang gonad (siap mijah) dapat ditemukan di semua stasiun penelitian. Seluruh lokasi penelitian merupakan habitat pemijahan ikan bilih. Juvenil ikan bilih hanya ditemukan di stasiun 3, 4, 5 dan 6. Oleh karena itu, diduga stasiun 1 dan 2 merupakan daerah pemijahan bagi ikan bilih sedangkan stasiun 3, 4, 5, dan 6 merupakan daerah pemijahan sekaligus juga daerah asuhan ikan bilih.Kata Kunci: Habitat pemijahan; asuhan; indeks gonadosomatik; juvenil; kelimpahan ABSTRACT Bilih fish (Mystacoleucus padangensis) is a species of the Cyprinidae family that have migration pattern from the lake to the river for spawning purpose. Spawning and nursery ground of bilih fish needs to be assessed before making a recovery effort of bilih fish in Lake Toba. The purpose of this study was to determine the nursery and spawning ground of bilih fish. Spawning ground is determined based on the number of mature gonad fishes and the nursery ground identified based on the presence of juvenile fishes in the Naborsahan

Pensi (Corbicula moltkiana) is the name a kind of freshwater mussel, which inhabit the Lake Maninjau, West Sumatra Province, Indonesia. Pensi has been utilized and important for the people in the Lake Maninjau region. The pensi fishing activities continuously will impact to their availability in the future. The purpose of this study is to observe the characteristics of pensi fishing activity in Lake Maninjau. The research conducted at the Maninjau Lake area, District of Tanjung Raya, Agam Regency West Sumatera Province from September 2013 to May 2014. The type of data collected is primary data with a focus on the dimensions and fishing pressure. Measurement methods used are interviews, data collection from fishermen and direct observations in the field. The data collected is then analyzed with descriptive methods. Pensi fishing activities as livelihood relatively available in the region Maninjau, especially for people who have no alternative other business fields. Average catches Pensi by fishermen was 51 liters (L) or 42 kg per day, and total production for all fishermen in Lake Maninjau region is 750 607 kg (751 tons) per year.