We applied Rabinowitz's rarity classification scheme to rocky intertidal algae from the Pacific coast of Japan between 31°N and 43°N to: (1) classify species in terms of rarity, (2) determine whether differences exist in taxonomy, functional grouping, and algal body size among rarity categories, and (3) examine the relationship between community properties (algal coverage and species richness) and the number and proportion of rare species. The presence or absence of each algal species and total algal coverage were determined for 1500 quadrats located on 30 rocky shores in May and July 2003. For the 83 eulittoral species found in at least three quadrats, we determined habitat specificity (wave exposure and tidal height), abundance (occurrence in the available habitat), geographic range (latitudinal range), and rarity category. The largest rarity category contained species with "large geographic range, broad habitat specificity, and low local density" and comprised almost half of the species. The second largest rarity category contained common species with "large geographic range, broad habitat specificity, and high local density". We found no differences in species characteristics among the major rarity categories. However, the number and proportion of rare species were positively correlated with algal species richness at the shore level.

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Four years after establishment, we surveyed the flora in 25 herbivore exclosures constructed using deer-proof fences in three plant community types (Miricacalio-Fagetum crenatae, Corno-Fagetum crenatae, Chrysosplenio-Fraxinetum) in the cool temperate zone of the Tanzawa Mountains. The area is inhabited by a high density of sika deer (Cervus nippon Temminck). In total, we identified 334 plant species, including 12 species considered endangered in the Kanagawa Prefecture. The Miricacalio-Fagetum crenatae community had the highest proportion of endangered species (5.1%). In addition, five species that had disappeared and six previously unrecorded species were found in the exclosures. Our results suggest that deer-proof fences, which prevent deer from grazing in an area, are effective in the restoration of these plants.

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In May 2004, the "Invasive Alien Species Act" was enacted in Japan with the aim of preventing adverse effects to ecosystems, human safety, agriculture, forestry, and fisheries caused by alien species. Here, we present a list of invasive alien vascular plant species that should be designated as Invasive Alien Species (IAS). Invasive alien vascular plant species were categorized according to the following four criteria: (1) the national or international status of invasiveness; (2) the total amount of riparian habitat that the species can invade; (3) adverse effects on biodiversity and ecosystems; and (4) the implementation of countermeasures by administrators or local residents. We selected 108 vascular plant species as IAS candidates and categorized them into three ranks (A, B, or C) according to the summed scores of the four criteria. Rank A consisted of the 16 most invasive species: Ambrosia trifida, Eragrostis curvula, Robinia pseudoacacia, Sicyos angulatus, Solidago altissima, Egeria densa, Festuca arundinacea, Myriophyllum aquatica, Elodea nuttallii, Eichhornia crassipes, Dactylis glomerata, Bischofia javanica, Taraxacum spp., Veronica anagallis-aquatica, Stenactis annuus, and Pistia stratiotes. These 16 species have demonstrated strong adverse effects on biodiversity and ecosystems, and programs have been implemented to control them. Almost all of these species are included in lists of the world's worst 100 invasive species and Japan's worst Invasive Alien Species, and most of them dominate large areas of riparian habitat. Rank B consisted of 34 species, including Barbarea vulgaris, Amorpha fruticosa, Gymnocoronis spilanthoides, Iris pseudacorus, and rank C consisted of 58 species. Some IAS candidates are currently used in landscaping and gardening. For conservation of biodiversity and ecosystems, all listed species, particularly those of rank A, should be designated as IAS, and active management must be implemented for their control.

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We quantitatively collected macrobenthos in 10 tidalflats from the Ryukyus Islands to Hokkaido, and compared species richness, biomass, species diversity and evenness, and number of endangered species between the tidalflats. Species diversity indices were calculated for each tidalflat by the number of species and ratios of wet weight for each species. Biomass classified the tidalflats into the clam-, polychaete-, and others-dominated. One or some of rhizopods, crustaceans, snails, polychaetes, and fish was/were dominant in the others-dominated one(s). Clams or snails were dominant in the most sandy tidalflats and polychaetes were in the most sandy-muddy and muddy ones. There was a positive relationship between the average number of species sampled per area (species richness) and the wet weight collected per area (biomass). Evaluations of species diversity by Shannon-Wiener's H′, E, Simpson's D and relative abundance curve were generally consistent one another. However, the trends of these parameters were not necessarily consistent with the trends of species richness and biomass. Endangered species were most abundant in two tidalflats from the Ariake Sound which evaluations were neither high with respect to species richness nor biomass. Besides, in one of these tidalflats the evaluations were low with respect to indices of species diversity. The results suggest that multi-dimensional comparisons are needed to evaluate the benthic community in the tidalflats.

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We developed three microsatellite markers to aid in the determination of genetic diversity and pollen flow in natural populations of a threatened perennial herb, Primula sieboldii. We determined the genotype of 52 genets in the University Forest of the University of Tsukuba, located on Mt. Yatsugatake in Nagano Prefecture, Japan. The markers were highly polymorphic; the observed number of alleles and heterozygosity per locus were 8-12 and 0.77-0.94, respectively. The combination of these three microsatellite markers and seven markers developed by Isagi et al. (2001) resulted in a probability of paternity exclusion of 0.997, and the probability of assigning a false paternal candidate by chance was improved from 84% to 7%. Therefore, the markers described here will be useful to reveal pollen flow in natural populations of P. sieboldii.

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Since about 1955, there has been increased revegetation of areas throughout Japan, including eroded hillsides and manmade slopes along roads. Grassland areas affect the feeding habits of the sika deer, Cervus nippon. We observed a tame female, 'deer D', in grasslands in revegetated areas on Mt. Tonotake, and examined the standing crops of the three major types of understory vegetation that occurred in the research area. In winter, deer D fed on dwarf bamboo leaves for 77 to 84% of its feeding time. In summer, the main food of this deer was grass in the revegetated areas, on which it spent 45 to 75% of its feeding time. The standing crops of two species of understory vegetation, Sasa hatatae and Calamagrostis hakonensis, began to decrease in October. Meanwhile, the standing crops of the revegetated grassland species continued to increase until November, despite high, continuous grazing by deer. The home range of deer D was very small (1.6ha in summer and 4.0ha in autumn), and the locations of the core areas of its habitat were determined by its food habits. The movement of deer D was reduced in the season when deer depended on a single vegetation source, such as dwarf bamboo or revegetated grassland. The results suggest that the revegetated grassland was a high-quality sustainable feeding area for deer D, which also affected its range and movement patterns. In areas where sika deer occur, revegetated areas of pasture may improve the nutritional status of deer and increase their densities above the carrying capacity. Deer habitat must be managed after considering the size and location of revegetated areas.

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Focus of nature restoration projects The following entities and interactions that constitute ecosystems should be included in nature restoration projects as far as possible: 1. Species and their habitats 2. Community structure and interspecific relationships 3. Ecosystem functions 4. Relationships between ecosystems 5. Sustainable relationships between humans and nature Clarification of aims and sharing of information Before nature restoration measures are carried out, the following actions should be taken at the project planning stage, and relevant information should be shared with all stakeholders: 6. Investigate the current situation of flora, fauna, and habitats according to scientific standards and examine the necessity of restoration measures. 7. Project the future development under the assumption that no action is taken, and if restoration measures are carried out, make the reasons for doing so clear. 8. Clarify the characteristics of the ecosystem that is to be restored, taking into consideration its spatial and temporal dimensions as well as the regional context. 9. Consider the extent to which natural succession should be controlled. Principles for nature restoration projects The following principles should be strictly adhered to when carrying out nature restoration projects: 10. Conserve plants and animals indigenous to a certain region (principle of conserving regional races). 11. Conserve all species constituting typical biological diversity for a certain region (principle of conserving species diversity). 12. Conserve the genetic variability of the population in a certain region (principle of conserving genetic variability). 13. Rely on natural recovery wherever possible, and avoid interference with natural processes (principle of natural recovery). 14. Cooperate with researchers from different disciplines (principle of multidisciplinary cooperation). 15. Respect traditional techniques of natural resource management and their cultural background (principle of respect for traditions). 16. Assess the feasibility of restoration goals (principle of feasible goals). Adaptive management The following adaptive management methods should be employed in nature restoration projects in order to allow for the unpredictability of ecosystem development: 17. Ensure the transparency of the project process through evaluation by third parties. 18. Employ the precautionary principle to avoid irreversible damage to ecosystems. 19. Set a concrete target that can be evaluated in the future. 20. Indicate the degree of uncertainty in the predictions of the management plan. 21. Test the hypotheses on which the management plan is based through monitoring, and adapt management measures according to the observed ecosystem changes. 22. Improve management measures or stop the project if the initial hypotheses prove to be wrong. Guidelines for consensus building and cooperation Nature restoration projects should be carried out according to the following rules and procedures: 23. Ensure that scientists play an adequate role. 24. Educate future generations who will bear responsibility for the project. 25. Build trust and consensus among stakeholders in the project area. 26. Establish links with other projects working for environmental conservation.

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In January 2004, 13 dead Pinus armandii var. amamiana trees and seven dead P. thunbergii trees were found in the new population of P. armandii var. amamiana that had been discovered in the Kinari National Forest on Tanega-shima Island, southwestern Japan, in September 2003. Bursaphelenchus xylophilus, the pathogen causing pine wilt disease, was detected in wood chip samples from seven of ten dead P. armandii var. amamiana and six out of seven dead P. thunbergii. To prevent pine wilt disease from spreading in this population, all of the dead pine trees were felled and cut into logs approximately 50cm in length, and all logs and branches >1cm in diameter were removed from the forest by local volunteers in March 2004, then were used as firewood at "Tanega-shima Yaki" pottery. Based on these activities, we present management schemes for local NPOs and governments for monitoring and eradicating trees infected by pine wilt disease in order to conserve the natural population of P. armandii var. amamiana.

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Recently, the introduction of conservation biology in conservation education has been desired for the practical conservation of the biological diversity. As a part of the conservation biology of Kirikuchi charr Salvelinus leucomaenis japonicus, the southernmost population of genus Salvelinus, we have initiated this education program for primary school children in the region. The proposal of education using Kirikuchi charr originated from a conference held between our research body, the fisheries cooperative, and the board of education in the region. As the first step of our education programs, we aimed at developing the interest of the children in Kirikuchi charr and/or the nature of the region. In order to achieve this aim, we conducted the education program, which had a high weightage attached to the experiences of the children; for example, the children were permitted to feel and observe the investigation tools and were made to view a video of Kirikuchi charr swimming in the river. It is considered that the aim of the program could be achieved because of the feedback from the children in terms of humorous, yet interesting questions and comments. With regard to the future, we will gradually have to continue the education programs for appropriate purposes. Hereafter, conservation ecology will play an increasingly important and indispensable role in conservation education.

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The popularity of ecotourism in Japan has recently increased; however, it may have detrimental effects on ecosystems because of the exhaustive use of natural areas. Field observations of the effects of ecotourism on nature were conducted at Hinai River and an adjacent area on Iriomote Island, Okinawa, Japan, in January 2004. The identified human impacts on the target areas were likely caused in part by the lack of an appropriate design for sustainable use in ecotourism. Ecotourism in developed countries such as Japan should be redesigned with consideration for their different socio-economic situations compared to developing countries for which ecotourism has become adapted. Currently, ecotourism in Japan is not consistent with the sustainable use of nature, because ecotourism has stronger detrimental effects on the ecosystem than did previous types of uses of these natural areas.

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"Sika deer problems" in Japan are primarily thought of as pest problems affecting agriculture and forestry, although attention has recently been given to their effects on natural vegetation. In decision making regarding deer problems, the opinions of urban residents have relatively little influence. A problem that must be taken into account when planning deer management programs is the concern that sika deer are destroying natural habitats in Japan and therefore cannot be allowed to increase in number. There is also conflict between agriculture-oriented offices, which target damage control, and conservation-oriented offices, which target biodiversity conservation. Local officers are often influenced by mass communication, which may oversimplify the issue as one of deer population problems. Important information needed for effective deer management includes the proper evaluation of damage, vegetation, and deer habitats. Deer population assessment is of low priority. It is necessary to avoid repeating previous mistakes that considered deer population to be a high priority issue. Continuous monitoring by wildlife specialists for at least five years is essential.

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In July 2004, a large resort hotel opened on the estuary of the Urauchi River, Iriomote Island, Japan. The distinct environment of this area, which includes many endangered species, makes it important academically. However, no study has examined the environmental impact of development of this resort. Academic associations have claimed that the company and politics prevented an environmental assessment. The Ecological Society of Japan has founded a committee to examine the follow-up activities of public requests for development. Several types of investment, including academic studies to obtain basic information and public announcements, may have some effect on conservation. Hereafter, political investments of society and the social activities of specialists as independent individuals should play an important role in promoting conservation in this area.

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