Penetasan telur penyu sisik (Eretmochelys imbricata) dengan kedalaman yang berbeda

This research was conducted from November 2018 until January 2019 which was held at the UPTD Conservation and Supervision of Marine Resources and Fisheries in West Sumatera, Pariaman City. The aim of the research is to know hatchling hawksbill sea turtle eggs based on nest depth. The method used in this study is a nonfactorial randomized block design (RBD) consisting of 3 treatments and 3 replications. The treatments used were treatment A (with a depth of 30 cm incubation nest), treatment B (with a depth of incubation nest 40 cm), and Treatment C (with a depth of incubation nest 50 cm). The results of this study showed that hatching hawksbill eggs hatched very significantly, the best hatching percentage was in treatment A (30cm) with 78% hatching at 6:00 a.m. with hatching temperature range of 24-28oC, hatching pH of 6,6-6,8 and medium sized incubation sand with a size of 0.150 mm with a weight reaching 461 grams.Keywords: Hatching percentage, Hawksbill turtle, pH, Temperature

Kajian kinerja pertumbuhan dan kelangsungan hidup ikan kerapu macan (Ephinephelus fuscogusttatus) menggunakan pakan hewani yang berbeda

The tiger grouper (Epinephelus fuscoguttatus) is an economically important fish whose fry still relies on natural catches. Several species of grouper are very potential to be cultivated because of their fast growth, efficient feed conversion, and high selling value. The purpose of this study is growth performance and survival rate tiger grouper (Epinephelus fuscoguttatus) used different live feed. The research design used in this study was a Completely Randomized Design with 3 treatments 3 replications and continued with LSD test if there were differences. The treatments given are treatment A (Snail), treatment B (Chicken Intestine), and treatment C (Caterpillar Maggot). Parameters observed were length increase, weight gain, survival, feed response, and water quality. The results of this study indicate that the highest increase was found in the treatment of C: 4,04 cm and the lowest was in treatment B: 3 cm, the highest weight gain was found in the treatment of C: 3,73 grams, and the lowest was in treatment B: 2,18 grams. The survival rate for all treatments is 100%. During this study the temperature ranged (28.6-31.8 oC), pH (6.7-8.2), DO (6.3-8.1 ppm), and salinity (23-27 ppt).Keywords: growth, live feed, survival rate, tiger grouper.

The Influence of Feeding Combination Silkworm (Tubifex sp.) with Commercial Feed on Growth Performance of Catfish (Clarias sp.)

This study aims to determine the growth of catfish (Clarias sp.) Seeds by giving a combination of silkworms (Tubifex sp.) and commercial feed. This research was conducted in August - October 2020 in the fish farming group of PT ASABRI, West Ilir II Palembang, South Sumatera. The treatments used in this study were 100% silkworm (control) feeding and a combination of feed treatment consisting of 75% commercial feed and 25% silkworms. Parameters include absolute weight growth, absolute length growth, feed efficiency, survival, and water quality. The results obtained from this study indicate that combination feeding (P1) obtained better results than the control (P0) with absolute weight growth data of 8.38 g, absolute length 7.39 cm, feed efficiency 56.38% and survival 87.50%.Keywords: catfish, commercial feed, combination, growth silkworm

Komunitas makrozoobentos dan kaitannya dengan kualitas air aliran sungai Senggarang, Kota Tanjungpinang

Senggarang is one of the coastal villages in Tanjungpinang City which has a river that flows from the upstream downstream into the sea. The flow of the Senggarang river has distinctive characteristics that are commonly found in small island waters, namely having a relatively short upstream to downstream distance, and the downstream part is influenced by tidal conditions. Various activities along the Senggarang river flow would cause changes in water quality which would impact the presence of macrozoobenthic. The objective of this study was to determine the relationship between the macrozoobenthic community and the water quality of the Senggarang river. Macrozoobenthic sampling, and environmental parameters were carried out using random sampling methods. The results of this study were obtained 27 species from 6 phylum, namely phylum Arthropoda 13 species, phylum Ciliophora 3 species, phylum Echinodermata 1 species, phylum Mollusca 4 species, phylum Nematoda 5 species, and phylum Tardigrada 1 species. The average macrozoobenthic density is 172 ind./ m3 for freshwater and 704 ind./ m3 for brackish waters. The average diversity value for freshwater is 1.29 and 2.16 waters with medium salinity, the average uniformity value of 0.85 freshwater and 0.94 of high in brackish waters, the average dominance value of 0.32 freshwater and 0.13 of low in brackish waters. The relationship of macrozoobenthos with the quality of freshwater based on PCA analyses related to temperature and dissolved oxygen, in brackish waters to temperature, dissolved oxygen, and current.Keywords: Macrozoobenthic community, PCA, River flow, Water quality

Contribution to the current list of Nitzschia species (Bacillariophyceae) in Malaysia

Current occurrence of Nitzschia Hassall from marine and freshwater environment in Malaysia is compiled from current and previously published materials. Phytoplankton was collected using a 20 µm plankton net from waterfronts of Peninsular Malaysia and Borneo. Some Nitzschia cells were successfully isolated and established into clonal cultures. For morphology observation, organic matters of the net samples and cultures were oxidized and removed through acid treatment. Cleaned specimens were observed using light and electron microscopes. The morphology of the Nitzschia cells was described and micrographs are included. In addition to current field sampling, Nitzschia spp. records and distributions in Malaysia had also been compiled from secondary data. Sources of references whereby the Nitzschia species were listed in this article were cited accordingly. This article compiles a total of 11 Nitzschia spp. found in Malaysia including a few revisions and new records. This article could serve as an important reference for Nitzschia taxonomic and distributional study particularly in tropical region.Keywords: distribution, morphology, taxonomy, tropical

The rhetorical blue economy in Bangladesh: Analyzing the inborn regulatory bottlenecks

This study's overreaching objective was to assess the suitability and applicability of the existing legal and institutional framework for managing the coastal and marine resources in Bangladesh. Together with, the fundamental challenges faced by the artisanal and small-scale fishers in Bangladesh were critically scrutinized. The study revealed that the regulatory framework in Bangladesh is characterized by jurisdictional overlapping followed by the conflict of interests among the public institutes, which originated from the aged and fragmented laws and ambiguous business allocation; consequently, the artisanal and small-scale fishers suffer a lot. The local government and community's right to resource management remains fuzzy. Bangladesh can enact new sectoral laws followed by business reallocation for the line ministries. The study will help policymakers identify the bottlenecks rooted in the existing regulatory and institutional framework.Keywords: Coastal and Marine Resource; Jurisdictional Overlapping; Conflict of Interests; Marine Governance; Artisanal Fishers

First Observation of the Nocturnal Cleaning Relationship between Common Octopus Octopus vulgaris (Cuvier, 1797), and Indo-Pacific Palaemonid Shrimp, Urocaridella pulchella Yokeş & Galil, 2006 from the Iskenderun Bay, Eastern Mediterranean Coast of Turkey

During a Scuba survey in Iskenderun Bay at night time on November 2018, a female Urocaridella pulchella individual was observed with nocturnal cleaning on Octopus vulgaris at 16 m in depth. Some photos of the shrimp and its symbiont were taken. Although the nocturnal cleaning relationship between U. pulchella and various marine species has been reported in some studies, the nocturnal cleaning relationship between O. vulgaris and U. pulchella has been observed for the first time. In addition, in the present study, we first reported Indo-Pacific palaemonid shrimp U. pulchella which was encountered in its natural habitat during an underwater observation from Iskenderun Bay, and this report is the first observation for this area and fills a gap in the distribution range of this species.Keywords: eastern Mediterranean, Iskenderun coast, nocturnal cleaning, Palaemonidae, Turkey.

Growth, Mortality and Exploitation Rate of Pagellus bellottii Harvested from the Marine Territorial Waters of Sierra Leone

The study investigated growth, mortality and exploitation rate of Pagellus bellottii collected off Sierra Leone, aimed to support efficient management of its stock. A total of 8, 216 specimens of Pagellus bellottii were collected at random from January-November, 2016 on-board a demersal trawler. Data analysis employed methods implemented in the computerized FiSAT II software using pooled length-frequencies in constant class size. Growth parameters gave asymptotic length (L∞ = 33.63cm), growth rate (K = 0.63yr-1), growth performance index (ɸ = 2.85), theoretical age (to = -0.6years) and life-span (tmax = 5.50years) whereas the length (Lm50) and age (tm50) at first maturity were estimated as 22.40 cm and 2.30years respectively. Besides, the current fishing mortality rate (F = 6.58yr-1) exceeded the optimum (Fopt = 0.50yr-1), limiting (Flimit = 0.81yr-1) and natural (M = 1.22yr-1) mortality rates, and the current exploitation rate (Ecurrent) was 0.84yr-1. Results depicted low life expectancy, fast growth and late first maturity (Lm50 = 33.4%, but < L∞) in Pagellus bellottii. Also, the stock of P. bellottii was overexploited (Ecurrent > 0.5), buttressed by the alarming current fishing mortality beyond optimal and permissible limits. This was very worrisome and the current exploitation rate should be reduced to 0.5yr-1 (40.5%) and fishing mortality rate to 0.5yr-1 (92.4%) in order to achieve at least optimal level of exploitation (Ecurrent = 0.5) and fishing mortality rate (Fcurrent = Fopt) respectively, through institution of closed fishing seasons and reduction in fleets targeting the species.Keywords: Exploitation; growth; life-span; mortality; stock

Respons fisiologis benur udang vaname (Litopenaeus vannamei) terhadap penambahan kalsium selama adaptasi di salinitas rendah

The purpose of this study was to determine the optimum addition of calcium during the adaptation period of white shrimp seed in low salinity media, so the physiological conditions of shrimp still support maximally survival and growth. The research was carried out by using the Completely Randomized Design, i.e., the addition of calcium in freshwater for decreasing water salinity from 20 g L-1 to 0.5 g L-1 as much as 150, 200, 250, 300, and 350 mg L-1, respectively. The freshwater used in the salinity reduction process was based on previous research that included sodium and potassium additions of 75 mg L-1 and 50 mg L-1, respectively. The test animal was a white shrimp stadium PL15 that had been acclimated for 5 days to a medium salinity of 20 g L-1. The results of this study showed that the addition of 300 mg L-1- calcium in freshwater during the adaptation for 96 hours significantly accelerate the achievement of molting time (1360 minutes), suppress the stress levels and metabolism rate (body fluid glucose of 169.80 mg L-1 and oxygen consumption level of 0.95 mg O2 g-1 h-1), and produce the highest survival rate of white shrimp seed (99%).Keywords: adaptation, calcium, low salinity, physiology, white shrimp

Occurrence of the Histioteuthis reversa (Verrill 1880), (Cephalopoda/Histioteuthidae) in the Gulf of Mersin/ Turkey

A different species of squid was caught during trawling (36°01’390’’N; 033°44’220’’E and 36°07’080’’N; 034°00’920’’E) in the Gulf of Mersin at average depth of 300-400 m. It was determined that this squid was Histioteuthis reversa (Verrill 1880). This is the first record of Histioteuthis reversa both for the Gulf of Mersin and Turkey's Mediterranean coast.Keywords: Coast of Turkey, Mediterranean, Priacanthus sagittarius, Spread.