The indigenous fishes of the Lake Biwa Basin, including endemic species that have arisen during the lake's 4 million year history, are now experiencing rapid declines in abundance. The introduced bluegill sunfish, Lepomis macrochirus, is a major factor contributing to the declines of native species. In line with recent legislation to regulate introduced species in Japan, and in particular to reduce the prevalence of bluegill in this and other water bodies, studies are needed to assess its risk of habitat utilization. However, there has been no catchment-scale assessment of bluegill habitat preferences in Japan. In this study, we evaluated the risk of habitat utilization by bluegill in the Lake Biwa Basin (including the Seta River and the Daido River) using logistic analysis. We used data on freshwater fish occurrence and habitat conditions from 2814 sites that were collected over 7 years by the Lake Biwa Museum Fish Survey Group. There were 14 environmental and temporal factors that significantly affected the risk of habitat utilization by bluegill. For example, the risk of habitat utilization by bluegill was 2.5 times greater in water deeper than 90 cm than it was in shallower places, and the risk in water shallower than 30 cm was 20% of that in areas deeper than 30 cm.

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To evaluate the accuracy and representative nature of data from citizen-based monitoring of seagrass beds, we compared census data taken by the Jangusa-Watch Program of the Nature Conservation Society of Japan at a seagrass bed in Okinawa Island, Japan, with remote sensing data from fine-scale, high-resolution aerial photographs taken with a digital camera attached to a blimp. Both monitoring and remote sensing quantitatively addressed the decline in seagrass coverage from 2004 to 2005 due to frequent typhoon disturbances. Citizen monitoring also revealed temporal changes with respect to species diversity and coverage of individual species, phenomena that could not be detected with remote sensing techniques. The remote sensing analysis identified patches as small as 1m^2 and the transition processes of each patch, such as emergence, extinction, fragmentation and persistence. Coverage quantified by monitoring and by remote sensing were significantly positively correlated in most cases. The degree of correlation varied with the observation area in the aerial photographs, and the pattern of area-related variation differed between years. Integrating citizen-based monitoring and remote sensing techniques offers a promising way to elucidate the spatial dynamics of seagrass beds, given that our understanding of this topic is limited when based on a single technique.

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A valuable source of vegetation occurs on a floating mat consisting of sphagnum peat in Mizorogaike Pond (Kyoto, Japan). To clarify the effects of sika deer on the floating mat, we used motion-sensor cameras to photograph sika deer in 2005. We obtained 33 pictures of sika deer, most taken at night. We established a 1×1600 m belt transect and investigated the spatial distribution of plant species and feeding scars. Fourteen herbaceous plants had feeding scars from sika deer ; Menyanthes trifoliata and Iris laevigata had feeding scars in 50% or more of the sub-transects (1×10 m, N = 160). We suggest that sika deer use the entire floating mat for feeding because feeding scars on M. trifoliata, I. laevigata, and Isachne globosa were ubiquitous. These dominant species had feeding scars in 10% or more of the sub-transects. Sika deer are considered ecosystem engineers ; severe feeding pressure by sika deer may change the vegetation in the Mizorogaike Wetland. To conserve the Mizorogaike Wetland, a deer exclosure fence must be established, and vegetation and deer effects, as well as water quality effects, in the Mizorogaike Wetland must be studied.

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We analyzed 135 dog fecal pellets sampled in a forest on Amami-Oshima Island, Japan. Rare mammals, including the Amami rabbit (Pentalagus furnessi; 45.2%), Amami spinous rat (Tokudaia osimensis; 23.7%), and long-haired rat (Diprothrix legata; 20.0%), occurred in fecal pellets at high frequencies, indicating that these species are highly vulnerable to dog predation. Dog reproduction in the forest area has not been confirmed. However, many pets or hunting dogs appear to be abandoned or unsupervised, indicating that the morals of pet owners may largely influence the dog population and, hence, its impact on native species. We propose the following management strategy. 1) Long term: preventing dogs from entering the forest. Enforcing current laws regarding supervision of dogs and educating pet owners is required. These are fundamental actions that will reduce the abundance of dogs in the forest; thus, this should be given high priority. 2) Short term: rapid action against detected dogs. A system to report dog sightings is necessary, together with a system to quickly catch reported dogs.

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The exotic annual Ambrosia trifida has recently invaded riverside vegetation that is dominated by Phragmites australis and Miscanthus sacchariflorus along the Omogawa River in the Kofu Basin, central Japan. The riverside vegetation is burned every winter in the downstream area, and nutrient-rich water flows into the river from nearby fruit farms. The distribution and structure of plant communities, growth of A. trifida, and environmental conditions were studied in the mid- to downstream reaches of the river to determine the effect of human-induced disturbance and the microenvironment on A. trifida invasion. A. trifida occurred more frequently downstream than midstream. Burning improved light and temperature conditions on the soil surface, thereby promoting the germination and growth of A. trifida. Canonical correspondence analysis of the community structure and the microenvironment in a Phragmites-Miscanthus community invaded by A. trifida indicated that the micro-distribution of native species primarily depended on soil moisture, but the micro-distribution of A. trifida did not. A. trifida grew taller in the middle of the P. australis and M. sacchariflorus habitats, indicating that interspecific interactions were more important for the growth of A. trifida than environmental factors. Most of the A. trifida seedlings that germinate and grow in burned sites are suppressed by competition from the native perennials that emerge later, although some seedlings may grow to dominate in vegetation gaps. Therefore, soil disturbance that destroys the rhizome system of perennials may facilitate the invasion of A. trifida.

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Recently, management and conservation have received much attention; the focus has been, mainly, on ecosystem and landscape functions and dynamics. Forest ecosystems are a major component of many landscapes; thus, forest management geared to maintaining ecological integrity is very important for conserving diversity at the gene, species, population, and community levels within the forest ecosystem, and also for conserving the regional landscape within which the forest ecosystem exists. This approach is called ecosystem-based management. In British Columbia, Canada, a variety of forested ecosystems occur, including forests dominated by infrequent large-scale fires, dry open forests maintained by frequent low-intensity fires, and coastal temperate old-growth rain forests characterized by small-scale gaps. That is, the predominate disturbance regime differs among regions within the province. To prevent ecosystems from deviating from their natural range of variability as a result of management, which undervalues the dynamic aspects of ecosystems, and also to restore the integrity of forest ecosystems, which already deviate from their natural range of variability, scientific research on natural disturbance regimes is becoming much more important so that ecosystem-based forest management in each region within the province may be achieved. At present, forest managers in British Columbia recognize the importance of the dynamic aspects and diversity of forest landscapes, factors that have been revealed through scientific research, and they have implemented adaptive management, improving management strategies through "learning by doing". As shown here, the integration of new knowledge gained from research into actual management strategies is very important to sustainable forest management.

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The 'ezo' eight-barbell loach, Lefua nikkonis, is endemic to Hokkaido, Japan. Although it is categorized as a vulnerable species in the Japanese edition of the Red Data Book, little is known about its distribution or habitat. Therefore, we examined (1) their habitat in Hokkaido and (2) their distribution within and around Nopporo Forest Park, Ebetsu-City, Japan. In the first experiment, we sampled ten points within five water systems where L. nikkonis had previously been collected. Fish were collected in traps and then released. We also documented the physiological conditions and water quality at each sampling point. L. nikkonis were found at five sampling points and dominated the fish fauna at these sites. The following environmental conditions characterized sites where loaches were collected: (1) gentle running water or pools in ditches, or ponds, (2) water with high chemical oxygen demand and with hypoxia in the bottom layer. In the second experiment, we collected loaches from 18 sites in Nopporo Forest Park. More individuals were collected in reservoirs than elsewhere ; we also collected loaches in the downstream reaches of these reservoirs. The reservoirs were swamp-like ; therefore, we collected other swamp-dependent fish species, including near threatened species, at these sites. Swamp conditions are generally deteriorating due to human activity, but the endangered species we came across may be found in other unregulated swampy reservoirs. To conserve L. nikkonis and other swamp-dependent species in Hokkaido, the surviving species should be studied, and reservoirs and ponds should be conserved.

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We censused herbivory on Cirsium lucens var. opacum by sika deer at Katsuragawa, Shiga Prefecture, Japan, in 2006. Of these plants, 30-60% had leaf damage and 46-70% had capitula damage. There was no difference in herbivory among the three habitats. Two plants decreased about 30-50% in height from 1997 to 2006. Bombus diversus, which was a common pollinator in 1997, was not found in 2006. The diversity or density of pollinators possibly decreased between 1997 and 2006. Seed set has possibly declined due to herbivore damage and pollinator decline.

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The environmental preservation investigation conducted by the Japan Green Resources Agency has a number of shortcomings. In addition, the rationality of the plan, in general, has been questioned by concerned citizens. As a result, a political movement requesting withdrawal of the plan has begun, with citizens cooperating with scientists. What stance should ecologists take in relation to this movement? Let us consider this problem as a case study.

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The western lowland of Yakushima Island, the World Natural Heritage area, is covered by broad-leaved evergreen forest subjected human disturbance, such as cultivation and wood charcoal production. However, details of the forest utilization remain unclear, because most of this area has been owned privately with no available track records for land use. Comprehension of the past human impact is required to understand the current forest condition and to develop an effective conservation scheme. We conducted field work and literature survey, including interviews with local people, in order to review the history of forest utilization in Han-yama and Kawahara sites in the western lowland of Yakushima Island. Results of literature survey and treering core analysis suggested that people appeared to first colonize these sites around 1900 to undertake cultivation, wood charcoal production, and camphor distillation. According to information gleaned from local people as well as aerial photos taken in 1947, areas totaling 32.2 ha in Kawahara have been clear felled for military purposes in the early 1940s. From the scattered distribution of abandoned charcoal kilns in the gaps of logged areas shown in aerial photos, it was deduced that almost the entire area of Han-yama and Kawahara sites experienced logging of varying intensity for charcoal and wood pulp between the 1940s and the end of the 1950s. Except for the road construction in 1967, these sites have been free from organized logging since around 1960.

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