The capacity of an environment to sustain large carnivores depends on ecological parameters such as carrying capacity and spatial requirements, as well as on the level of social acceptance of those species. Social acceptance varies depending on factors such as local conditions, economic aspects, and predator density, and often is an ultimate factor limiting population numbers of large carnivores independently of ecological conditions. Within protected areas, all basic factors, i. e. carrying and spatial capacities, and social acceptance of large carnivores, have generally higher values, thus potentially allowing for the maintenance of viable populations of those species. Unfortunately, strictly protected areas such as national parks are, in most cases, too small to fulfil that role. There is only limited potential left in Europe for further extension of national parks, even if forests with low productivity or extensive agricultural areas are considered. Existing protected areas are already surrounded by intensively managed or densely inhabited environments. An optimal solution for the problems facing large carnivores seems to be the introduction of the concept of Large Carnivore Conservation Areas, encompassing ranges trespassed on and occupied by large carnivores, as a supplementary system for already existing protected areas. A strictly protected area, such as a national park, would then serve as core zone, and the sub-optimal surroundings could be included as a buffer or a transition zone. Since such designated zones would have differing values in terms of their environmental capacity, various management options, appropriate to protected status, habitat, and economic conditions, are suggested. Such methods may facilitate the enlargement of potential ranges of large predators, facilitate their movements between their core areas, and alleviate conflicts with people thereby making possible the ultimate goal of species conservation-the creation of conditions adequate for the maintenance of a viable population.

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Seven prawn species (Macrobrachium equidens, M. esculentum, M. lanchesteri, M. mammillodactylus, M. mirabile, M. sintangense, and M. rosenbergii) occur in the rice fields, canals, and rivers of the Mekong Delta. The SDS-PAGE method of protein analysis was firstly applied to the structural protein of antennae in order to re-examine the classification of species and to seek diversity and genetic differentiation among them. Six traits were estimated, e. g. coefficient of variance (CV), phenotypic diversity (Ho), genetic diversity (H_EP), percentage of polymorphic individuals, percentage of polymorphic bands, and the sum of the effective number of alleles (SENA). Research revealed that M. equidens has the lowest level in all six traits, indicating that its population is declining dramatically. In addition, the genetic pool of M. rosenbergii in this region was decreased significantly due to farmers catching for cash. A phylogenetic tree was constructed based on protein analysis, which confirmed and extended the classical classification of prawns in the Mekong Delta. The seven species fall into two groups based on their protein phenotypes and ecological adaptations. The results of this research will be useful for prawn conservation and breeding in the near future.

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To conduct preliminary studies of food conditions for sika deer Cervus nippon in the eastern part of the Tanzawa Mountains, we analysed crude protein (CP), fiber, calories, and in vitro digestible dry matter (DDM) using the rumen fluid of sheep on evergreen broadleaf tree species, deciduous tree species, grass and forbs. Significant positive correlations were found between CP content and neutral detergent solubles {100 - (neutral detergent fiber)} (r = 0.38, n = 114), among fiber contents (r = 0.52 to 0.78, n = 92), between calorie and fiber content (r = 0.36 to 0.48, n = 92) and between CP and DDM (r = 0.49, n = 84). Significant negative correlations were shown between CP and calories (r = -0.42, n = 114), CP and fibers (r = -0.32 to -0.41, n = 114), between DDM and calories (r = -0.31, n = 84), and between DDM and fibers (r = -0.46 to 0.77, n = 84). A predictive equation (r² > 0.82, p < 0.001) for dry matter digestibility from CP, silica, and fiber composition was developed. We then discussed the nutritional values of several food items for free ranging sika deer and their connection with habitat use.

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The authors listed hydrophyte communities and surveyed their distributions along the Yongsan River and its tributaries, southwestern Korea, between March 1996 and October 1999 by using phytosociological methods. In total 23 hydrophyte communities were found: they were grouped into 4 submerged hydrophytes, 5 floating leaved hydrophytes, 10 emergent hydrophytes, 3 free-floating hydrophytes, and the Salix gracilistyla community. Surveys of seven river-crossing profiles showed that those hydrophyte communities, the Salix gracilistyla community, and three man-made habitats were regularly distributed from the upper stream to the estuary of the main river and from the stream to the banks depending on the water depth, water flow speed, stream width, and land development along the river. In the flood plain between banks of the middle and lower river, crop lands, sports parks, car parks, cycling roads, dams, reservoirs, and sewage drains have occupied, destroyed, and badly affected habitats of the native hydrophyte communities. Thirteen hydrophyte and other communities were surveyed in the 15 tributary rivers of Yongsan River. Among those communities, three hydrophyte communities, Zizania latifolia, Paspalum distichum, and Potamogeton crispus communities, were commonly found predominating in 11 or 12 of the 15 tributary rivers, and the others were found in fewer than five tributaries, seemingly dependent on the extent of land development.

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The ecosystem of Uotsuri-jima, one of the islands in the Senkaku Archipelago, off southwestern Japan, has probably been devastated by a dramatic increase in goats (Capra aegarus) since their deliberate introduction in 1978. Because the Senkaku Islands are claimed as national territory by China, Taiwan, and Japan, scientific researchers have been unable to land on Uotsuri-jima, nor have there been opportunities to eradicate the goats there. The effects of the goats on the vegetation of the island were assessed therefore using remote-sensing techniques: aerial photographs, Landsat satellite images, and an IKONOS satellite image. The results showed that bare patches have emerged in several areas, and that particular floral communities on the raised coral reefs may have already been lost. Since the flora of the sub-canopy layers are not visible beneath the dense forest canopy that covers most of the island, using current remote-sensing methods, very little is known about the extent of damage to the flora of these layers. Land-based surveys are thus urgently required to assess the condition of the flora and to control the introduced goats.

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