Publications by authors named "Yasushi Mitsunaga"

Understanding the mechanism by which non-native fish species integrate into native communities is crucial for evaluating the possibility of their establishment success. The genus Pangasianodon, comprising Pangasianodon gigas and Pangasianodon hypophthalmus, has been introduced into reservoirs, which are non-native habitats, for fishery stock enhancement. P.

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Article Synopsis
  • A new method for measuring fish bioelectric signals using one internal electrode and one external electrode in seawater could help manage farmed fish health and improve understanding of wild fish physiology.
  • Initial attempts didn’t reliably capture ECG R-waves, but researchers found that positioning the internal electrode near the heart improved results for multiple fish species.
  • The optimized method allows for simultaneous ECG measurements of several fish with just one external electrode, making it more efficient than traditional techniques.
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  • Dietary information from aquatic organisms helps predict interactions and understand ecosystem functionality, especially in freshwater habitats with generalist fish species accessing diverse food sources.
  • This study focuses on striped catfish feeding habits at different life stages, using isotopic and fatty acid analysis to differentiate their food sources from various chains.
  • Findings reveal that adult catfish rely on primary photosynthetic food sources, while juvenile catfish utilize both anoxic decomposition and photosynthetic production, highlighting the importance of anoxic food chains in tropical fish diets.
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The Mekong giant catfish (MGC), Pangasianodon gigas, is one of the world's largest catfish species. Endemic to the Mekong River system, the MGC is critically endangered. Six MGC were transported from Thailand to the Gifu World Freshwater Aquarium (GWFA) in Japan in May 2004.

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Fish form schools because of many possible reasons. However, the hydrodynamic mechanism whereby the energy efficiency of fish schools is improved still remains unclear. There are limited examples of fish models based on actual swimming movements using simulation, and the movements in existing models are simple.

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The Mekong giant catfish is one of the largest freshwater fish, measuring up to 3 m in total length. This study was designed to determine the feeding habits of to better understand how the fish achieve their large body size. We compared the relationship between gut length (GL) and total length (TL) among related species in superfamily Bagroidea, order Siluriformes ( and ) in the Kaeng Krachan reservoir, Thailand.

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The vertical movements of one Mekong giant catfish Pangasianodon gigas were monitored for 3 days in August 2004 using a depth-temperature micro data logger. The logger was recovered using an innovative time-scheduled release system and located by searching for VHF radio signals. The logger was found approximately 2.

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For conservation and successful stock enhancement of endangered species, an understanding of the movement patterns and behavior of the target species is indispensable. The Mekong giant catfish, Pangasianodon gigas, is endemic to the Mekong Basin and now is threatened with extinction. Although biotelemetry using acoustic transmitters and receivers is expected to reveal its movement patterns and behavior, the most suitable attachment method for the transmitter to the catfish is unknown.

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