Yudha, Hirmawan Tirta
Pusat Penelitian dan Pengembangan Perikanan, Badan Penelitian dan Pengembangan Kelautan da

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GROW-OUT OF ABALONE Haliotis squamata IN FLOATING CAGES FED DIFFERENT PROPORTIONS OF SEAWEED AND WITH REDUCTION OF STOCKING DENSITY Giri, I Nyoman Adiasmara; Sutarmat, Tatam; Yudha, Hirmawan Tirta; Rusdi, Ibnu; Susanto, Bambang
Indonesian Aquaculture Journal Vol 9, No 1 (2014): (June 2014)
Publisher : Pusat Penelitian dan Pengembangan Perikanan, Badan Penelitian dan Pengembangan Kelautan da

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (64.904 KB) | DOI: 10.15578/iaj.9.1.2014.15-21

Abstract

Abalone is a herbivore marine animal which feeds on seaweed. Abalone culture has a good prospect in terms of price, market share and simple culture technique. Thus, a study was conducted with the aim of finding out an effective and efficient abalone culture technique in terms of feed use and density. In this study, a 42 cm diameter plastic container with a 22 cm height was used. Three vertically arranged containers were used as the experimental group which were put into a net box and hung onto a raft so that the containers were placed in a 4 m depth below the sea surface. The juvenile of abalones being used came from a hatchery production that has been adapted to cages environment with Gracilaria sp. and Ulva sp. feed. The initial density of abalones was 450 for each container, with the initial weight of 2.6-3.2 g and the 2.5-2.7 cm shell lengths. The abalones were fed with Gracilaria sp. and Ulva sp. seaweeds with different Gracilaria sp./Ulva sp. proportions, i.e. 100/0% (A); 80/20% (B); and 60/40% (C) as the treatments. Each treatment consisted of two replications. After three months of rearing period, densities of abalones were reduced to be 190 for each experimental unit. Weight and shell length of abalones were measured every month by measuring 25 abalone samples from each experimental unit. The result of the experiment showed that the increase in the Ulva sp. proportion in the feed increased the growth of abalones and decreased the feed conversion. Feeding with Gracilaria sp./Ulva sp. proportion of 60%/40% allowed the best growth of abalones. The decrease of abalone density in the experimental unit after three months of rearing also produced an increase in their growth.
FREQUENT MONITORING OF WATER TEMPERATURE IN PEGAMETAN BAY, BALI: A PRELIMINARY ASSESSMENT TOWARDS MANAGEMENT OF MARINE AQUACULTURE DEVELOPMENT Radiarta, I Nyoman; Erlania, Erlania; Sugama, Ketut; Yudha, Hirmawan Tirta; Wada, Masaaki
Indonesian Aquaculture Journal Vol 9, No 2 (2014): (December 2014)
Publisher : Pusat Penelitian dan Pengembangan Perikanan, Badan Penelitian dan Pengembangan Kelautan da

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1126.007 KB) | DOI: 10.15578/iaj.9.2.2014.177-185

Abstract

Aquaculture currently share for nearly half of the world’s food fish consumption, and continue to be the fastest-growing animal food producing sector. The viability of aquaculture operation has greatly been affected by the characteristic of marine environment. Inventory and monitoring of marine environment are necessary and can be done through information technology implementation. Frequent monitoring of water temperature, for almost one year observation, at four aquaculture sites in Pegametan Bay and Research and Development Institute for Mariculture was investigated. Water temperature data were obtained by using logger and buoy systems. These data were contrasted against marine fish mortality. On the other hand, the suitability of species requirements with the thermal conditions was evaluated by comparing temperature range to the optimum and lethal temperature information available on marine fish species of aquaculture interest. This research could be beneficial for enhancing productivity of marine aquaculture operation in terms of possible impact of climate change. It was also possible to find the ideal temperature range for culturing fish species, taking into account the variability associated with large-scale phenomena.