Diversity, Distribution Pattern, Morphometric of Box Mussel Septifer Bilocularis (Linnaeus, 1758) on the Reef Flat in Cape Lampangi, South Minahasa

Septifer bilocularis (Linnaeus, 1758) is a suspension feeder organisms which are found live clustered on dead coral . This study aims to estimate the average density, analyzes the distribution patterns and analyze morphometric aspects of a long-high (thick) relation, length-total weight relation and length-weight index without shell relation of S. bilocularis at that location. Sampling method using transect squares method, with the length of each line is 50m, on each transect placed 10 squares (measuring 1m x 1m). Based on the data analysis of the average density in both transect was 214 individuals with a clustered deployment pattern, with a maximum shell length of 29,64mm. The relation between length and high of shell shows that the growth is allometri negative, length and total weight shell relationships is allometri negative, where the contents of the weight index does not increase with increasing length but declined. Box mussel Septifier bilocularis live clustered with very dense aggregations in intertidal reef flat area on the intertidal zone are exposed at the lowest tide at Cape Lampangi

Community Structure of Gastrpods in Mokupa Beach, Sub-district of Tobariri,Minahasa Regency, North Sulawesi Province

Ecologically intertidal mollusk has important role in the food chains. As a filter feeder, mollusk is also known as a food source for other marine organisms. The intertidal zone is known as the smallest area in the ocean basin (Nybakken, 1992). This zone is a narrow edge cover only few square meters and position between low tide mark (LTM) and high tide mark (HTM). The study was conducted in Mokupa beach waters, Tombariri sub-district, Minahasa Regency. Coastal area of Mokupa village represent typical tropical ecosystem such as coral reef, seagrass bed and mangrove belt. As many as 45 species in 134 total individuals were recorded during the study. The density of gastropods collected is 4.4667 individual/m2 while density for gastropods species Littoraria scabra Linne was 0.4000 individual/m2 and in term of relative density is 9.834 % and thus considered the highest. Species diversity index of this species is H\u27 = 2.37594. Keywords: mollusk, diversity, dominance A B S T R A K Secara ekologis Moluska yang menempati daerah intertidal memiliki peranan yang besar kaitannya dengan rantai makanan. Karena di samping sebagai filter feeder, moluska juga merupakan makanan bagi biota lainnya. Zona intertidal (pasang-surut) merupakan daerah terkecil dari semua daerah yang terdapat di samudera dunia (Nybakken, 1992). Zona ini merupakan pinggiran yang sempit sekali, hanya beberapa meter luasnya, terletak di antara air pasang tinggi dan air surut rendah. Penelitian ini dilaksanakan di perairan pantai Mokupa Kecamatan Tombariri Kabupaten Minahasa. Daerah pantai Desa Mokupa merupakan daerah yang lokasinya terdapat ekosistem yang khas di daerah tropis yaitu terumbu karang, padang lamun, dan hutan mangrove. Diperoleh sebanyak 45 spesies dan berjumlah 134 individu. Kepadatan rata-rata organisme Gastropoda diperoleh 4,4667 indv/m2 , dengan kepadatan spesies tertinggi 0,4000 indv/m2 (Littoraria scabra Linne), dengan Kepadatan relative adalah 9,834 %.Keanekaragaman spesies diperoleh nilai (H\u27= 2.37594

Longitudinal Distribution and Morphometric Character of Eel at the Downstream Site of Kabur River, East Likupang, North Minahasa

Eel is a unique organism that grows in the freshwater habitat and when they have reached adult stage of life they will migrate thousands of kilometers to the sea for spawning. This research was aimed at identifying the eel species, defining the breadth composition of longitudinal distribution, describing and analyzing the relationship between length and weight (alometric, isometric growth) and the conditional factors, and determining the feeding habit of eels hauled in Kabur river, Rinondoran village, East Likupang District, North Minahasa Regency, North Sulawesi Province. The samples have been collected in April 19th 2015 based on the river length survey method. The hauling process was started at the downstream site which then headed to the upstream. The result of the research showed that there were two (2) species of eel that have been hauled they are Anguilla marmorata and Anguilla celebesensis. The value of F-count 3 ). The average condition factor of every class of the total A. marmorata length is from 0,1691 to 0,2426. In general, the kinds of food usually consumed by the eels are shrimp, worm, and crab. Based on the index of preponderance, the highest percentage of diet is crab. Therefore, crab becomes the main diet with IP value of 78,2. Keywords: Eel, size, growth, conditional factor, feeding habit A B S T R A K Sidat adalah organisme unik yang bersifat katadromous yaitu tumbuh di habitat air tawar dan ketika dewasa akan bermigrasi ribuan kilometer untuk mengadakan pemijahan di laut. Penelitian ini bertujuan yaitu mengidentifikasi spesies sidat, menentukan komposisi ukuran sebaran longitudinal, mendeskripsikan dan menganalisis hubungan panjang berat (pertumbuhan alometrik, isometrik) serta faktor kondisi, menentukan kebiasaan makanan sidat yang tertangkap di Sungai Kabur, Desa Rinondoran, Kecamatan Likupang Timur, Kabupaten Minahasa Utara, Provinsi Sulawesi Utara. Pengambilan sampel dilakukan pada tanggal 19 april 2015 berdasarkan metode survei sepanjang sungai. Penangkapan di mulai dari hilir sampai menuju hulu sungai. Hasil penelitian menunjukkan bahwa ada dua spesies yang tertangkap yaitu Anguilla marmorata dan Anguilla celebesensis. Nilai F-hitung 3). Nilai faktor kondisi rata – rata pada masing - masing selang kelas panjang total A. marmorata yaitu dengan kisaran antara 0,1691 - 0,2426. Secara keseluruhan makanan yang paling sering dijumpai pada lambung A. marmorata adalah udang, cacing, dan kepiting. Berdasarkan nilai indeks bagian terbesar (Indeks of Preponderance), persentase tertinggi terdapat pada jenis makanan yang berupa kepiting, dengan demikian kepiting menjadi makanan utama dengan nilai IP yaitu 78,2

Community of Starfish in the Coastal Area of Mokupa Village, Sub-district of Tombariri, Minahasa District, North Sulawesi Utara

This study was carried out in the coastal waters of Mokupa, Tombariri District, Minahasa Regency, North Sulawesi Province. It was aimed to know the sea star community. The study was beneficial as information source of the sea star. Data collection employed a quadrat-transect method in new moon and full moon. There were 3 sampling points randomly selected. Each transect was placed 10 1x1 m quadrats along 100 m-transect seaward. The species found were Protoreaster nodosus, Linckia laevigata, Archaster typicus, Culcita novaeguineae, Pentaster obtusatus. Higher mean number was found in new moon than in full moon. The dominant species in Mokupa waters was Protoreaster nodosus

Allometry Analysis and Physiological Index of Sea Urchin Heliocidaris Crassispina (a. Agassiz, 1864) (Camarodonta, Echinometridae) on the Reef Flat in Tongkeina and Malalayang Dua, Manado, Sulawesi

The purpose of this study was to analysis the structure of the size, morphometry (test diameter-high relationship, test diameter-weight relationship) as well as gonad indices, intestine indices, and Aristotle lantern indices of Heliocidaris crassispina in two different habitats, Malalayang Dua and Tongkeina. At each habitat, free sampling on the reef flat have be done one time for approximately two hours at the lowest tide. The abundance of individuals H. crassispina in Malalayang Dua was much lower than in Tongkeina. The means diameter of sea urchins test were not significantly different between habitats. The comparison of regression lines of both diameter-high and diameter-weight relationships were not differ significantly between habitats. Its morphometry reveal an isometric relationship of high-diameter (slope = 1) in both habitats, while the relationship of weight-diameter reveals a negative allometric growth (slope < 3) in Tongkeina but isometric growth in Malalayang Dua. The gonad index in Malalayang Dua was higher than in Tongkeina. The intestine index in Tongkeina was higher than in Malalayang Dua. The lantera index in Tongkeina was higher than in Malalayang Dua. The difference in abundance of sea urchins and the acquisition of the energetic value of food presumably serve as the factors affecting the differences of these indices and its weight growth pattern. _______________________________________________________________