The complex multi-gear, multi-species tropical fisheries in developing countries are poorly understood and characterising the landings from these fisheries is often impossible using conventional approaches. A rapid assessment method for characterising landings at fish markets, using an index of abundance and estimated weight within taxonomic groups, is described. This approach was developed for contexts where there are no detailed data collection protocols, and where consistent data collection across a wide range of fisheries types and geographic areas is required, regardless of the size of the site and scale of the landings. This methodology, which was demonstrated at seven fish landing sites/fish markets in southern Indonesia between July 2008 and January 2011, provides a rapid assessment of the abundance and diversity in the wild catch over a wide variety of taxonomic groups. The approach has wider application for species-rich fisheries in developing countries where there is an urgent need for better data collection protocols, monitoring future changes in market demographics, and evaluating health of fisheries.

Tongkol komo (Euthynnus affinis) merupakan komoditas perikanan ekonomis penting. Di Selat Malaka sumber daya tongkol komo merupakan stok bersama antara Indonesia dan Malaysia yang telah dimanfaatkan secara intensif dengan berbagai alat tangkap. Dalam rangka pengelolaan sumber daya  ikan tongkol komo di Selat Malaka supaya tetap lestari, penelitian ini dilakukan dengan tujuan memperoleh informasi mengenai parameter populasi, aspek biologi dan aspek penangkapan. Penelitian dilakukan secara observasi, enumerasi dan wawancara. Hasil penelitian menunjukkan nilai berbagai parameter populasi; panjang maksimum tercapai (L) = 64,25 cmFL, laju pertumbuhan (K) = 0,96/tahun, laju kematian alami (M) = 1,38 /tahun, laju kematian karena penangkapan (F) = 1,41/tahun, panjang pertama tertangkap (Lc) = 34,5 cmFL dan panjang pertama matang gonad (Lm) = 41,02 cmFL dan laju pengusahaan (E) = 0,50. Dari aspek biologi diperoleh; nisbah kelamin betina : jantan =1 : 1,15, puncak gonad matang dan indek kematangan gonad terjadi pada Maret dan November, mangsa dominan ikan teri (Stolephorus sp.). Alat tangkap utama untuk penangkapan tongkol komo berupa pukat langgai (purse seine). Nilai CPUE tertinggi diperoleh pada Juli dengan musim penangkapan terjadi pada periode April-Juli. Kontribusi tangkapan ikan tongkol komo sebesar 17,42-27,20 % dari total tangkapan ikan. Jenis ikan tangkapan utama yang berinteraksi dengan tongkol komo adalah kembung (Rastrelliger sp.) dan layang (Decapterus sp). Parameter yang bersifat negatif  terhadap kelestarian populasi ikan tongkol komo, seperti ukuran ikan dan hasil tangkapan per unit usaha nilainya kecil. Parameter yang bersifat positif antara lain; rasio antara nilai kematian alami dengan nilai laju pertumbuhan masih dalam kisaran normal dan nilai tingkat pengusahaan masih dalam kisaran optimum. Penangkapan ikan tongkol komo di Selat Malaka masih dalam keadaan normal, tetapi perlu pengawasan terhadap mata jaring dan alat tangkap yang digunakan serta aktifitas penangkapan pada musim pemijahan. Adanya interaksi dengan jenis ikan pelagis kecil dan dominasi ikan teri dalam isi lambung, sehingga dalam pengelolaan ikan tongkol komo harus dilakukan bersama dengan kedua komoditi. Mackerel tuna (Euthynnus affinis) is an important economic fishery commodity. In the Malacca Strait, mackerel tuna  resource is a share stock between Indonesia and Malaysia that has been used intensively with various fishing gear. In order to manage the fish resources of  mackerel tuna  in the Malacca Strait to be sustainable, this research is conducted with the aim of obtaining information on parameteer population, biology aspects and fishing aspects. The research was conducted by observation, enumeration and interview. The results showed the values   of various population parameters: length infinity (L”) = 64.25 cmFL, growth rate (K) = 0.96/year, natural mortality rate (M) = 1.38 /year, capture mortality rate (F) = 1.41 /year, length of first captured (Lc) = 34.5 cmFL and length of first maturity (Lm) = 41.02 cmFL and exploitation rate (E) = 0,50. Biological aspect was obtained; sex ratio female : male = 1: 1.15, peak of mature gonad  and index gonad maturity occurred in March and November, main prey are anchovy (Stolephorus sp.). The main fishing gear for catching mackerel tuna is purse seine. The highest CPUE value was obtained in July with the fishing season occurring in the April-July period. The contribution of catch mackerel tuna are 17.42-27.20 % of the total catch of fish. The main species of fish that interact with mackerel tuna  are mackerel (Rastrelliger sp.) and sardine  (Decapterus sp). Negative parameters to sustainability of mackerel tuna population such as fish size and catch per unit effort are small. Positive parameters are the ratio between the value of natural mortality and the rate of growth is still within the normal range and the level of exploitations rate is still within the optimum range. The fishing of mackerel tuna in the Malacca Strait is still in normal condition, but it is necessary to monitor of the nets mesh size and fishing gear used and fishing activity on spawning season. The existence of interaction with small pelagic fish species and the dominance of anchovy in the contents of the stomach, so that in the management of mackerel tuna fish should be done together with the two commodities.

Ikan tongkol komo (Euthynnus affinis)  termasuk salah satu ikan pelagis ekonomis penting yang tertangkap di Laut Jawa. Data dan informasi tentang  ikan tongkol komo di Laut Jawa masih terbatas, sehingga perlu dilakukan penelitian biologi ikan ini. Penelitian beberapa aspek biologi ikan tongkol komo dilakukan dari bulan Januari sampai Desember 2012. Penelitian ini bertujuan untuk mengetahui beberapa aspek biologi tongkol komo yang meliputi  hubungan panjang dan berat, nisbah kelamin, tingkat kematangan gonad, ukuran rata-rata pertama kali tertangkap dan ukuran rata-rata pertama kali matang gonad dan kebiasaan makan. Pengukuran panjang  ikan dilakukan secara acak proporsional, sampel ikan dibedah untuk  mengetahui kematangan gonad, nisbah kelamin, dan jenis makanan. Hasil penelitian menunjukkan sebaran frekuensi panjang ikan tongkol komo antara 13-55 cm dengan modus  25 cm. Pertumbuhan tongkol komo bersifat isometrik dan perbandingan jumlah kelamin jantan dan betina menunjukkan nisbah kelamin dalam kondisi seimbang. Ukuran rata-rata pertama kali  tertangkap (Lc) dengan mini purse seine adalah 31,75 cm. Ukuran rata-rata pertama kali matang gonad (Lm) adalah 33,7 cm. Ikan tongkol komo tergolong ikan karnivora yang mangsanya meliputi berbagai jenis ikan dan moluska.

Information on exploitation status of fourfinger threadfin (Eleutheronema tetradactylum Shaw, 1804) is important for sustainable gillnet fisheries management in Tarakan, North Kalimantan  waters. In an attempt of providing scientific data and information on the exploitation status of this species, a research work was conducted from January to November 2016 in Selumit landing place. Fish sampling was done by trained enumerator on bottom gillnet catches landed through semi-regular observation. A total of 1964 specimens were collected and measured. The results showed that the size ranged between 16-70 cmFL with an average of 37.72 ± 0.36 cmFL. The length at first captured (Lc) of about 38.5 cmFL, was smaller than the length at first mature of female (Lm) of 39.6 cmFL. The growth pattern was negative allometry. By applying von Bertalanffy growth model, it was found that growth model for this species was L(t)=75,8(1-e0,3(t+0,035)). Exploitation rate (E) was 0,47. It showed that the exploitation status of fourfinger threadfin in Tarakan Waters was still sustainable.

Udang windu merupakan salah satu komoditas ekonomis di Indonesia dan sudah dimanfaatkan serta dikembangkan cukup lama di perairan Tarakan sehingga perlu upaya pengelolaan dengan salah satu dasar kajian biologinya. Penelitian ini membahas beberapa aspek biologi udang windu, meliputi hubungan panjang-berat, nisbah kelamin, kematangan kelamin, serta ukuran rata-rata tertangkap dan matang kelamin. Penelitian dilakukan pada selama bulan Januari-November 2016. Hasil penelitian menunjukkan, dari 2208 ekor contoh udang windu yang dianalisa, ukuran yang tertangkap berkisar antara 21,9-63 mmCL serta hubungan panjang-bobot menyatakan pola pertumbuhan isometrik. Musim pemijahan diduga terjadi sepanjang tahun dengan puncak pemijahan pada bulan Maret-April dan September. Nisbah kelamin udang berada dalam kondisi tidak seimbang dan didominasi oleh betina. Rata-rata ukuran pertama kali tertangkap (Lc) adalah pada panjang karapas 40,69 mmCL serta rata-rata ukuran matang gonad (Lm) udang betina adalah 33,58 mmCL. Tiger shrimp (Penaeus monodon, Fabricus, 1789) was one of economic commodity of shrimp in Indonesia and had been exploited and developed for long time so that necessary management measure based on biology study. The aim of the research was to study of biology aspects of tiger shrimp such as length-weigth relationship, sex ratio, maturity stage and length of first capture (Lc) and length of first maturity (Lm). The research were carried out from January to November 2016 using survey method and the enumeration programme. The result of 2.208 sample of tiger shrimp analyzed showed that size of tiger shrimp between 21.9-63 mmCL with the growth follows a isometric trend. Spawning season occurs throughout the year with peak season in March-April and September. Sex ratio was in an unbalanced condition dominated by females. The length of first capture (Lc) was 40.69 mmCL and length of first maturity (Lm) was 33.58 mmCL.