Underwater noise of commercial vessels in Nusakambangan Strait and the relationship with distance

The existence of shipping activities can produce noise with certain characteristics as a main source of noise pollution in the waters. This research aimed to study the sound characteristics (frequency and sound pressure levels) of various type of commercial vessels crossing the Nusakambangan Strait, its relationship to the distance, and their potential impact to the marine biota. Noise frequency and sound pressure level were determined by spectral and envelope analysis from sound recording by hydrophone, while the type of vessel that produces noise and the distance from receiver were analyzed based on video recording. Relationship between frequency and sound pressure level to the distance were analyzed using simple linear regression. Results showed that frequency of noise is varied more clearly compared to the sound pressure level (1,7 – 20 kHz and 93.8 -117.8 dB re 1 μPa respectively) for each type of vessel (ro-ro ferry, small fishing boat, small ferry, tug boat and pilot boat) based on the size of the ship, engines type and power, loading capacity and vessels speed. Sound characteristics changed based on distance, where the frequency of sound increases (0.04 – 34.28 Hz.m-1) and different things for sound pressure level (0.04 – 0.11 dB dB re 1 μPa m-1). Estimated source level also differ from one ship to another (105 – 128 dB dB re 1 μPa). The existence of ship noise has the potential impacts on the presence of marine biota in these waters.

Effect of fish meal replacement with lentil seed (Lens culinaris) in common carp (Cyprinus carpio) L. diet

The aim of this study was to see how replacing fish meal with lentil seeds (LS) as an alternative plant protein source in diets for common carp Cyprinus carpio affected growth performance, feed consumption, and the composition of the fish's proximate carcass. The fish (100-106 g mean initial weight) were fed 0% (LS0), 5% (LS5), 10% (LS10), 15% (LS15) and 20% (LS20) of Lentil seed protein for 10 weeks. With increasing fishmeal replacement with lentil seed in the fish diet, there was a significant (p<0.05) increase in weight gain, relative and specific growth rate. T5 (20% LS) had a significantly (p<0.05) higher feed efficiency ratio and protein efficiency ratio than the other treated groups. There were no significant (p<0.05) differences in the mean values of proximate composition of fish fillets, such as moisture, crude protein, crude lipid and ash. Finally, no significant differences in muscle ratio (weight without viscera vs. weight without viscera & head) were found. The current study found that lentil seed can replace 20% of dietary fish meal in common carp diets for better growth.Keywords: lentil seed, fish meal, common carp, growth performance and feed utilization.

Productivity and Distribution of Fish Aggregation Devices (FADs) in Outer Ambon Bay Waters, Indonesia

Distribution of small pelagis fish in FADs, and produktivity of FADs in AmFADs are usually used by fishermen to concentrate fish for an efficient catching activity. However, the number, distance, and distribution in the waters need to be assessed in relation to the productivity of the FADs in order to maintain the sustainability. This study was aimed to map the distribution of FADs; to analyze the distribution of species, number and size of fish associated with FADs; and to calculate FAD productivity based on distribution in the Outer Ambon Bay waters. Data was obtained by observation and interview. Field observation, including: coordinates and number of FADs, species, number and size of fish. The distance and distribution of FADs, was mapped using software (Argis web), while the productivity of FADs was analyzed base on catch per unit effort (CPUE). The result, FAD in Outer Ambon Bay waters was found 25 unit and the average distance of FAD was obtained 0.47 nautical miles, and the placement of the device was irregular. The placement pattern of FADs were generally straight to coastline. Small pelagic fish was found 7 species and the 5 of the dominant species were obtained Decapterus sp, Selar crumenophthalmus, Rastreliger sp, Sardinella sp and Selaroides sp. The species were unevenly spread at each FAD with quite varied sizes. FAD productivity showed that the highest productivity was found in the middle group FAD at Ambon Bay waters.Keywords: Distance, size, small pelagis, productivitybon Bay

The Role of Filter with Different Media Compositions on Water Quality and Survival of Pangasius (Pangasius sp.) in Recirculation Aquaculture System

The high market demand for Pangasius (Pangasius sp.) has encouraged farmers to adopt a cultivation system with high stocking densities and high feeding rates. This causes fish farming waste to increase and ammonia in the waters also increases, resulting in a decrease in water quality. One of the efforts to overcome this problem is by using Recirculation Aquaculture System (RAS). This study aims to examine the effect of filters with different media compositions in RAS of Pangasius. Test fish, average weight of 4.59 g, kept for 30 days in aquarium with a density of 1.15 g.L-1. The feed is given at satiation, twice a day. There were five treatments and four replications during study. The treatments were the difference composition of filter media, i.e. A (100% zeolite), B (25% net + 75% zeolite), C (50% net + 50% zeolite), D (75% net + 25% zeolite), and E (100% net). Dacron was used as a mechanical filter in all treatments. The results showed that the composition of different filter materials had a significant effect (P <0.05) on Survival Rate (SR), Total Amount of Feed Fed (TFF), Relative Growth Rate (RGR), and Feed Conversion Efficiency (FCE). The best performance was showed by media biofilter composition of 25% nets + 75% zeolite, with the value of VTR (Volumetric Total Ammonia Nitrogen Removal) were 55.45-66.32 g.m-3.day-1, SR was 93.75%; TFF was 124.84 g; RGR was 2.13%.day-1, and FCE was 46.87%. Various different compositions of net and zeolite as filter media on RAS were able to manage TAN below tolerance limit.Keywords: catfish, recirculation system, filter composition, dacron, net, zeolite.

The Growth of Seriatopora hystrix (Dana, 1846) Transplant with Differences of Fragments Size and Planting Position

Transplantation of coral reefs requires sufficient fragments but must still ensure the sustainability of coral donors. This research aimed to know the survival rate and growth rate of transplant corals with different fragment sizes and planting positions and to determine the most effective and efficient transplantation methods of the Seriatopora hystrix. The research was conducted from January to April 2016 in Serangan Island waters Denpasar Bali (1-2 m depth). The method used was a field experiment with variations of planting position (vertical, horizontal) and fragment sizes (3, 5, 7 cm). The results showed a high survival rate (98.3%) of the transplanted S. hystrix with planting position and fragment sizes variation. The variation of planting position and fragment sizes were significantly affected the length growth rate of the S. hystrix (p <0.05). The vertical planting position showed better growth compared to the horizontal planting position. The transplantation of coral with initial fragment sizes of 5 and 7 cm showed a higher growth rate than the fragment size of 3 cm. However, statistical analysis revealed no significant difference between initial fragment sizes of 5 and 7 cm. Therefore, this study demonstrated the most effective and efficient for S. hystrix transplantation showed in the vertical position with the initial fragment size of 5 cm.Key words: coral bleaching, initial fragment, tropical, zooxanthellae

Spatio-Temporal Assessment of Zooplankton Fauna of Uta Ewa Estuary, Akwa Ibom State, Nigeria.

Estuaries are influenced by the mixture of river water with seawater; creating unique ecosystems with several physical and chemical processes affecting the water quality. Spatial and temporal assessment of the composition, abundance, and distribution of zooplankton fauna of Uta Ewa Estuarine water system was carried out between May 2019 and February 2020 to assess the effects of anthropogenic activities on the zooplankton assemblage. Water and Zooplankton samples were collected from three (3) stations using standard procedures. Some parameters like water temperature, dissolved oxygen, hydrogen-ion, electrical conductivity, and turbidity were determined in-situ. The ranges of the physico-chemical parameters were: water temperature (24.9-25.3oC), EC (62.3-70.9mS/m), pH (6.5-6.7), turbidity (12.0-28.0NTU), DO (3.8-4.7mg/L), BOD (2.3-3.2mg/L), phosphate (3.2-5.2mg/L), and nitrate (3.0-6.3mg/L). ANOVA showed a significant difference (p<0.05) in the spatial and temporal means values of some parameters. A total of 1,067 individuals from 30 zooplankton taxa and 4 taxonomic groups were recorded. Rotifers (33.4%) were the dominant group, followed by protozoa (32.9%), copepods (20.9%) and cladocerans (13.8%). Station 1 had the highest abundance (388 individuals), station 2 (303 individuals) and station 3(375 individuals). The higher number of individuals (193) was recorded in August 2019. The biodiversity indices pointed to slightly polluted to stable environment. This study showed that the water quality and zooplankton community was influenced by anthropogenic activities both spatially and temporally but season also played a major role in the temporal variation. In conclusion, the water quality was deteriorating due to anthropogenic activities, which in turn affected the structure of zooplankton community. Keywords: Abundance, Assessment, Zooplankton, Physicochemical, Estuary

Masculinization of Banggai Cardinalfish (Pterapogon kauderni) using 17α-Methyltestosterone-enriched Artemia sp.

Banggai Cardinalfish (Pterapogon kauderni) is one of the endemic fish from the waters of the Banggai Islands, Central Sulawesi Province. One factor challenging the production of P. kauderni larvae is the male fish will nurture the eggs and larvae for 30 days, hindering next spawning cycle. One effort to overcome this problem an increase of male fish number should be performed, for example through sex reversal. This study aimed to determine the effectiveness of the hormone 17α-methyltestosterone (17α-MT) through Artemia sp. to increase male sex percentage P. kauderni. This study used a completely randomized design by testing four treatments namely feeding Artemia sp. which has been soaked with 2.0 mg of the 17α-MT hormone for two- hours given to P. kauderni larvae for 10 days (A); 20 days (B); 30 days (C), and without hormone treatment 17α-MT (control). Each treatment included control was performed in triplicates. The percentage of male sex was 93.33 % at 30 days treatment and was higher (P<0.05) compared to controls (53.3 %). Additionally, the results showed that daily growth rate, biomass gain and survival rate of all treatments were not significantly different (P>0.05) with those of control. In conclusion, Artemia sp. contained 17α-methyltestosterone enhanced male percentage of P. kaurderni. Keywords: growth, male percentage, Artemia sp., survival rate, Pterapogon kauderni

Shoreline Change Analysis of Pontang Cape of Serang Regency of Banten Province

Coastal areas, being vulnerable to environmental problems, have one of the most frequent problems which are the change in the shorelines. Shoreline changes, namely abrasions, can cause problems such as land degradations or loss of land in a coastal zone. This problem occurs in many areas, one of which is Pontang Cape. This study aims to determine the distance and rate of shoreline changes that occured in the Cape and its surroundings, as well as explaining the analysis points based on similar studies that had been conducted. This research used ArcMap software and Digital Shoreline Analysis System (DSAS) toolset to determine the distance and rate of shoreline changes for 19 years (1999-2018). Based on the results, there were two shoreline segments where different phenomena of shoreline change took place, namely Banten Bay (accretion) and Pontang Cape-Lontar (abrasion). The most likely causes of changes in the shorelines are sediment runoffs from rivers that lead to bay and sediment transports that affect Banten Bay accretions, while sea sand mining and conversions of mangrove swamps into fishery ponds are factors affecting abrasions in Pontang Cape.Keywords: Abrasion, Accretion, Pontang Cape, Banten Bay, DSAS