Sahami FM, Kepel RC, Olii AH, Pratasik SB, Lasabuda R, Wantasen A, Habibie SA. 2020. Morphometric and genetic variations of species composers of nike fish assemblages in Gorontalo Bay Waters, Indonesia. Biodiversitas 21: 4571-4581. Nike is Gobioidei fish at the post-larval and juvenile stages whose habitat is still in seawater before they migrate to the freshwater, grow up, and spawn to fulfill their life cycle as an amphidromous species. This study aims to identify the species composers of Nike fish in Gorontalo Bay waters based on their morphometric and molecular characters. 2,523 samples were collected from the catches of fishermen during three periods of their appearance in Gorontalo Bay waters from January to March 2019. The samples were grouped based on their similarity of melanophore patterns, and morphometric characters of 10 units were then measured. This study found 20 different groups of melanophore patterns; 15 of them were new melanophore patterns. DNA samples from each group of new melanophore patterns were then isolated for molecular analysis. The morphometric analysis grouped the 20 melanophore patterns into three separate clusters that were confirmed through molecular analysis. The results of Gen Cytochrome Oxidase I (COI) sequences indicate that the new melanophore patterns of Nike fish assemblages consisting of six species; five species in the Gobiidae family (i.e. Sicyopterus parvei, S. cynocephalus, S. longifilis, S. lagocephalus, and Stiphodon semoni) and a species in the Eleotridae family (Belobranchus belobranchus).

Nike is a terminology used by Gorontalo local community to name schooling of minuscule amphidromous goby fish that has a limited appearance in Gorontalo waters. Understanding the biological performance of Nike fish is vital for implementing management and conservation strategy. This study aims to analyze daily recruitment and to determine growth patterns of Nike fish population in nature. Sampling was conducted in the Gorontalo waters during March, April, and May 2018 using a fish net with a mesh size of 0.5 inches. The duration of the appearance of Nike schooling in waters varies every month. The number of fish samples collected each month in this study ranged from 150 to 300 individuals. This study reveals that body color diversity and morphology of Nike fish strongly alleged to depend on where and how long they appear in the waters. Based on the daily recruitment pattern, Nike fish population distributed in Gorontalo waters is predicted to consist of individuals from multi-generation with an average length range of 1.848–2.805 cm. During the sampling time, a positive allometric growth pattern indicated by the population.

Fisheries and Aquatic Sciences

Judul : Level Kualitas Perairan Bagian Hilir Sungai Paguyaman, Gorontalo, Indonesia: Suatu Kajian Berdasarkan Distribusi Mikroalga dan Indeks SaprobikLatar Belakang: Sungai Paguyaman membentang sepanjang 136,25 km dan merupakan daerah aliran sungai terbesar kedua di Provinsi Gorontalo. Bagian hilir sungai ini bermuara di Teluk Tomini dan berada di perbatasan antara Desa Girisa Kecamatan Paguyaman Kabupaten Boalemo dan Desa Bilato Kecamatan Boliyohuto Kabupaten Gorontalo. Bagian hilir sungai ini menjadi sumber penghidupan bagi masyarakat di sekitarnya, namun kualitas perairannya terancam akibat pencemaran organik yang berasal dari aktivitas domestik dan pertanian. Tujuan dari penelitian ini adalah untuk mengidentifikasi jenis dan distribusi mikroalga, dan menilai kualitas perairan menggunakan indeks saprobik di wilayah hilir Sungai Paguyaman, Gorontalo.Metode: Pengambilan sampel dilakukan pada empat stasiun dengan masing-masing tiga ulangan, dimulai dari stasiun 1 tepat di bibir muara sungai, kemudian disusul stasiun 2 hingga 4 dengan jarak antar stasiun 3-4 km. Mikroalga yang diamati mencakup mikroalga planktonik (fitoplankton) dan mikroalga yang melekat pada substrat batu (perifiton). Sementara parameter fisik perairan mencakup kedalaman air, suhu, kecepatan arus, kecerahan, dan substrat dasar, serta parameter kimia perairan mencakup pH, oksigen terlarut (DO), dan salinitas.Hasil: Hasil penelitian menunjukkan bahwa mikroalga yang ditemukan di wilayah hilir Sungai Paguyaman berasal dari 10 kelas yang terdiri dari 101 spesies dan 45 genus. Komposisi terbanyak berasal dari kelas Bacillariophyceae.Simpulan: Berdasarkan nilai indeks keanekaragaman (H'), indeks dominansi dan indeks keseragaman mikroalga, perairan secara umum berada dalam kategori komunitas stabil dengan keberadaan atau kepadatan biota yang merata. Nilai indeks saprobik (SI) 1,64 dan nilai indeks keadaan trofik (TSI) 0,65 menunjukkan bahwa tingkat saprobitas wilayah hilir Sungai Paguyaman saat ini berada pada tingkat Oligo/b-mesosaprobik yaitu termasuk pada kategori tercemar ringan. Temuan ini mengindikasikan bahwa perairan di hilir sungai mengalami penurunan kualitas yang dapat berdampak pada kesehatan ekosistem dan masyarakat. ABSTRACT Background: Paguyaman River stretches for 136.25 km and represents the second largest drainage basin in Gorontalo Province. Its downstream area of the river empties into Tomini Bay and is located on the border between Girisa Village, Paguyaman Subdistrict, Boalemo Regency, and Bilato Village, Boliyohuto Subdistrict, Gorontalo Regency. This regions constitutes a vital source of livelihood for the local community. However, organic pollution from domestic and agricultural activities threatens the quality of its waters. The objective of this study is to identify the types and distribution of microalgae and assess water quality using saprobic index in the downstream area of Paguyaman River, Gorontalo.Method: Sampling was conducted at four stations with three replications per station. The sampling began at station 1, located at the river mouth, and continued to stations 2 through 4, with a distance of 3-4 km between stations. Microalgae observed included planktonic microalgae (phytoplankton) and microalgae attached to rock substrates (periphyton). The physical parameters included water depth, temperature, current velocity, brightness, and bottom substrate, while the chemical parameters included pH, dissolved oxygen (DO), and salinity.Result: The findings revealed that microalgae in the downstream area of the Paguyaman River came from 10 classes of 101 species and 45 genera. The most significant composition comes from the Bacillariophyceae class. Conclusion: According to the diversity index (H'), dominance index, and uniformity index of microalgae, the waters are generally classified as stable communities, characterized by the presence or density of biota that are evenly distributed. The Saprobic Index (SI) value of 1.64 and the Trophic Status Index (TSI) value of 0.65 indicate that the saprobity level of the downstream area of the Paguyaman River is currently at the Oligo/b-mesosaprobic level, which is included in the lightly polluted category. This finding indicates that the river downstream is experiencing degrading, potentially affecting the health of the ecosystem and the surround community.

Desa Dulangeya merupakan salah satu desa di Pesisir Kecamatan Botumoito, Kabupaten Boalemo. Salah satu potensi Desa pada sektor perikanan adalah ikan karang (batu) yang dijual dalam bentuk segar atau diolah secara tradisional menjadi ikan kering gantung. Teknik pengeringan secara tradisional memiliki kelemahan terutama dalam ketidakhigienisan produk. Kegiatan pengabdian kepada masyarakat ini bertujuan meningkatkan keterampilan masyarakat lokal dengan memberikan edukasi dan pelatihan tentang proses pengolahan ikan asap melalui pengaplikasian rumah asap model kabinet dan kemasan plastik vakum. Kegiatan ini dilaksanakan di Desa Dulangeya, Kecamatan Botumoito, Kabupaten Boalemo selama 45 hari. Pelatihan dilakukan dengan memberikan sosialisasi dan edukasi terkait produk olahan ikan asap yang dilanjutkan dengan kegiatan praktik pembuatan ikan asap dan pengemasan. Kelompok sasaran kegiatan yakni istri-istri nelayan di Desa Dulangeya. Melalui kegiatan ini, masyarakat Desa Dulangeya memperoleh keterampilan tambahan dalam membuat produk ikan karang (batu) asap khas Dulangeya. Masyarakat dikenalkan dan diberikan edukasi terkait proses pengasapan menggunakan rumah asap model kabinet tertutup sebagai upaya mengoptimalisasi pemanfaatan panas dan asap yang terperangkap. Selain itu, model konstruksi kabinet tertutup juga ditujukan untuk meminimalisasi kontak langsung produk dengan sumber-sumber pencemar. Masyarakat juga dilatih dan ditingkatkan keterampilannya dalam hal mengemas produk menggunakan alat vacuum sealer dan plastik vakum serta pemberian label kemasan, sehingga dihasilkan produk ikan karang (batu) asap yang higienis dan menarik. Dengan adanya kegiatan ini, masyarakat mitra kegiatan telah mampu membuat produk ikan karang (batu) asap yang higienis dengan kemasan plastik vakum dan label kemasan yang menarik sebagai produk inovasi yang diharapkan dapat meningkatkan perekonomian masyarakat lokal.

Graphical Abstract Highlight Research 1. The potential of coral reefs for marine tourism has been calculated. 2. The potential of coralfish for marine tourism has been identified. 3. Water quality parameters are supporting factors for the sustainability of marine tourism. 4. The suitability of snorkeling and diving tourism has been mapped. Abstract The waters of Tomini Bay, which boast the longest coastline in Gorontalo Province at 572.5 km, hold significant marine tourism potential, warranting further study and development. This research evaluated the potential and suitability of marine tourism in the Tomini Bay Gorontalo area, specifically snorkeling and diving. Data were collected on coral reef conditions, reef fish communities, and water quality parameters from six locations, including Pinomontiga, Kurenai, and Kaisomaru Beach, as well as Dulanga, Bitila, and Lahe Islands. Coral reef conditions were assessed using the underwater photo transect method, while reef fish data were collected using the underwater visual census method. Physical water parameter data measured were temperature (°C), salinity (‰), pH, dissolved oxygen (mg/L), current speed (cm/s), and brightness (m). The analysis of coral cover was conducted using Coral Point Count with Excel extensions (CPCe), while the suitability for snorkeling and diving tourism was assessed using the Tourism Suitability Index. The results showed that most locations had moderate to excellent coral reef conditions, high coral and fish diversity, and water quality that supported marine tourism activities. Among the six locations studied, two, namely Pinomontiga Beach and Lahe Island, were rated highly suitable for snorkeling and diving, while Kaisomaru Beach was not suitable. Other places, including Kurenai Beach and Bitila Island, were rated as suitable. These results provide essential information for developing sustainable marine tourism in Tomini Bay Gorontalo and can serve as a reference for local government in planning environmentally friendly tourism activities.