To contribute to improving eel stocking procedures, the survival, growth and behaviour of farmed Japanese eels reared together with wild individuals were evaluated to learn about possible encounters of farmed‐ and stocked eels with wild eels. Two experiments were conducted to evaluate the (a) effect of the presence of wild eels on survival and growth of farmed eels in experimental ponds and (b) behavioural differences between wild and farmed eels placed in a small tank. In the survival and growth experiment, significantly lower survival and growth rates of farmed eels reared with wild eels were observed compared with farmed eels reared without wild eels (control). In the behavioural observations, the authors observed significantly higher occupation rates of a refuge and more frequent biting for wild eels, indicating a dominance of wild eels over farmed eels. Because wild and farmed eels used in the current experiments belong to the same genetic population, these differences resulted within one generation through the aquaculture rearing process.

Distributions of seaweed/seagrass communities were determined from 230 sites along the coast of Kagoshima Bay, southern Japan, during a series of surveys in 2006. Sargassum (brown algae) and Zostera (angiosperm) communities were conˆrmed from 159 and 41 sites, respectively. Of the 19 species of Sargassum and Zostera conrmed in this study, distributional characteristics of 12 major species were also elucidated. Kagoshima Bay is comprised of three diŠerent areas (back, central part and mouth of the bay) as deˆned by the in‰uence of waters entering the bay from the Kuroshio Current. Two Zostera species, Z. marina and Z. japonica, and four temperate species of Sargassum, S. fusiforme, S. hemiphyllum, S. patens, and S. piluliferum, were conˆrmed from all areas.Meanwhile, six subtropical and warm-temperate species, S. alternato-pinnatum, S. crispifolium, S. cristaefolium, S. duplicatum, S. glaucescens, and S. incanum, were not detected in Kagoshima Bay except for some sites, as indicated by a previous survey in 1976; however, we detected them from various sites in the central part and mouth of the bay. We suggest that these species appeared and developed communities in the past 30 years.

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