Changes in the flora and the individual number of flowering plants under Sika deer browsing were investigated at Makura-dani in Ashiu Experimental Forest, Kyoto Prefecture, Japan. The number of species decreased from 84 to 56. Among the 77 species evaluated, eight species increased and 47 species decreased conspiciously in number, probably resulting in the local extinction of 22 species. The rate of species loss was greater for large-sized plants and the rate of unchanged or less changed species was greater for small-sized plants. Summer or autumn flowering herbaceous species showed higher rates of decreased species number than spring flowering species. Therefore, plant size and flowering season were the important characteristics for evaluating the browsing effect. The estimated number of flowering individuals and the Simpson's diversity index showed distinctly different phenological patterns after Shika deer browsing, and the seasonal function of flowering plant community on herbivorous insects visiting flowers were supposed to have changed.

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Objective methods are needed for identifying areas where control measures against invasive alien species should be focused. We investigated classification tree models of the distribution of invasive plant stands (Ambrosia trifida, Eragrostis curvula, Sicyos angulatus, and Robinia pseudoacacia) in riparian areas of the Chikuma River. For each taxon, we used Classification And Regression Tree (CART) analyses to relate the distribution of invasive stands to explanatory variables (relative height from calculated water level, vegetation type, distance to nearest agricultural fields, areas dominated by the target species around each grid cell, and areas dominated by the target species in upstream river regions of each grid cell) and to derive the potential distribution of the target species. The current distribution of invasive stands along the Chikuma River was largely explained by relative height. We compared model predictions by testing the agreement between observed and simulated distributions (using the area under the receiver operating characteristic curve [AUC], specificity, sensitivity, and correct classification rate) by assessing consistency. Our results demonstrated that this modeling approach, combined with the visual presentation of predictions as a map, provides useful information for making decisions with regard to how different conservation actions and flood protection measures should be spatially allocated.

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We investigated the fen communities and their hydrochemical environments in Abiragawa, which embraced the largest area of fens in Yufutsu district, and compared with communities growing in neighboring seven mires. Three groups were identified; Group A (Calamagrostis langsdorffii) predominantly occurred in floodplain mires and Group C (Carex lasipcarpa var. occultans) in valley mires. Two types of Group B dominated by Thelypteris palustris occurred exclusively in lower water level areas of Abiragawa. B1 had mixed species composition with Group A, and B2 with Group C. The EC and pH values in B2 were lower than B1. After the modification of river course in 1956, water supply to Abiragawa had interrupted. In Abiragawa, Group A is growing and one type of Group C was described on 1975. The dominance of Thelypteris, which grows in drier habitats indicates that the hydrological change could develop the communities of Group B by deteriorating the communities of Group A and C. The alder forest (Alnus japonica) has increased by 50% for the last 29 years and replaced fens, provably owing to hydrological changes. Accordingly, recovering the hydrological conditions before modifying rivers would be effective to restore fen communities in Abiragawa.

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The ages of 42 Tsushima leopard cats killed by traffic accidents between 1997 and 2008 were determined by counting cementum annuli and assessing body size and the condition of teeth replacements. Additionally, body condition was estimated by external veterinary examinations. We assessed the relationships between cat age and the occurrences of traffic accidents. The ages of cats ranged from 0- to 9-years-old, more than 70% of which were yearlings. However, 2- to 4 year-old cats were not found among the dead; thus, the age distribution of the accident victims was biased toward yearling and older individuals. Traffic-related mortality among male yearlings occurred frequently from autumn to winter (September-January) and did not overlap with the time of year when>1-year-old individuals frequently suffer from traffic accidents, except in September. Traffic-related mortality among yearling females occurred most frequently in November. Yearlings, which are generally born in spring and become independent of their mothers in autumn and winter, lack experience of artificial dangers such as cars. Furthermore, yearlings must make long trips to cross paved roads until they settle in their own home ranges. Thus, yearlings tend to frequently suffer from traffic-related accidents. The deaths of subadults without clinical problems and of resident cats in traffic accidents are likely to have negatively affected the population levels of this endangered species.

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The artificial lucidophyllous forest at the Miyazaki-Jingu Shrine, which was afforested about 100 years ago, has been preserved as fragmented forest in the city center of Miyazaki. We investigated the species composition, species richness, and life-form spectra of this artificial lucidophyllous forest and compared these factors among the four types of lucidophyllous forest (artificial, secondary, natural, and primeval forest) present in central Miyazaki Prefecture. In the artificial lucidophyllous forest, we observed 118 component species of lucidophyllous forests, including several endangered species. Of these 118 species, many shrubs and herbs had been dispersed by birds from the gardens of adjacent homes. Based on the formula, logS=1.16+0.20logA (where S is the number of species, and A is the area of the forest), derived from a study of the fragmented lucidophyllous forests in central Miyazaki Prefecture, the number of component lucidophyllous forest species was calculated as 158.6 at the Miyazaki-Jingu Shrine. The lower number of observed species, as compared to the number of calculated species, was likely to be due to the simple micro-scale geomorphic conditions at the Miyazaki-Jingu Shrine. The species richness (mean number of component species of lucidophyllous forests per 100m^2 stand) of the artificial lucidophyllous forest was lower than that of natural and primeval lucidophyllous forests but was similar to that of secondary lucidophyllous forests. In terms of life-form spectra, the Miyazaki-Jingu Shrine artificial lucidophyllous forest was characterized by the absence of vascular epiphytes and the scarcity of ferns.

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We investigated the records of 69 traffic accidents involving the Okinawa rail, Gallirallus okinawae, and the road conditions at the scenes of 36 of these accidents. We found that the location of these traffic accidents tended to move northward over the year. The accidents occurred mostly in May (30.4%) and June (30.4%), followed by August (13.0%). Most of the victims were adult birds of either sex, although chicks (in April), fledglings (in May and June), and juveniles (in July, August, December, and January) were also involved. The Okinawa rails were observed most frequently between May and July, and the number of tourists visiting the Yambaru area peaked in August. The monthly number of accidents was positively correlated with both the number of tourists visiting the Yambaru area and the number of rails observed along roads. Most accidents occurred on long and straight or gently curving roads, with high undergrowth along the sides, and without guard rails. These findings suggest that the risk of traffic accidents involving the Okinawa rail depends on the activities of the rail in relation to reproductive ecology, the volume of traffic in the Yambaru area, and the road conditions and the local environment, such as the access to roads. We propose that the risk of traffic accidents involving the Okinawa rail be managed by considering these factors.

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To assess the influence of witches' broom on the structure of bamboo forests, we evaluated the damage inflicted by this disease on bamboo plants and determined the species composition and species richness (number of species) of bamboo forests. Based on the degree of damage inflicted, bamboo forests were assigned to four transition phases: "normal", "infection", "dieback", and "restoration". During the transition from the normal to the dieback phase, coverage in the tree layer decreased by half and the number of species doubled as the extent of bamboo damage increased. In contrast, during the transition from the dieback to the restoration phase, coverage in the shrub layer rapidly increased tenfold, due to the regeneration of small bamboo culms, whereas the number of species decreased by half. These results indicate that witches' broom in bamboo plants has a transient positive effect on species richness in bamboo forests during the early phase of the disease but has a negative impact in the long term. After the restoration phase, bamboo forests are expected to succeed the pioneer community within a short period of time; however, over the long term, species-poor lucidophyllous forests would dominate.

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Salix hukaoana Kimura is an endangered riparian tree species whose distribution is restricted to the upper reaches of rivers and has only been reported from a limited number of river basins in the northern Kanto to Tohoku Districts. We assessed the geographical distribution of this willow primarily on the Japan Sea side of Tohoku District. Five populations were found in Akita and Yamagata Prefectures, and these included three newly-discovered populations that revised the northern limit of the distribution. Most of the populations were small and narrowly distributed, with the exception of the population in the Otorigawa River Basin, Yamagata Prefecture. The habitats of S. hukaoana were located at 170 to 640m a.s.l. and along reaches where the mean gradient of the valley bottom ranged from 2.0 to 0.5°. The warmth index at these habitats was estimated to be 59.9 to 87.8, and the maximum snow depth ranged from 217 to 361cm. These results suggest that the distribution of S. hukaoana includes environments on the Japan Sea side of northeastern Honshu but that the species is still geomorphologically restricted to narrow ranges; thus, appropriate conservation efforts are required.

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The introduction of the non-native bumblebee Bombus terrestris has resulted in the general decline of native bumblebees across Japan. The Nemuro Peninsula in eastern Hokkaido is one of the most important habitats for native bumblebees, as 10 of the 15 Japanese species, including the rare B. florilegus and B. hypocrita, occur in this region. We investigated the abundance and distribution of the 10 native species and B. terrestris throughout the Nemuro area from May to September 2009. We recorded over 1000 bumblebees on flowers during the study, including all 10 native species and B. terrestris. Although B. terrestris has just invaded the Nemuro Peninsula, it is already established throughout the entire region and is the dominant species in the center of Nemuro. We also confirmed that B. florilegus remained the rarest species with only two queens and 14 workers observed, all from coastal areas. The decline of bumblebees in the Nemuro area has already been affected by habitat degradation and fragmentation, but the rapid naturalization of B. terrestris across the entire peninsula will hasten the decline of other species, especially the rare B. florilegus and B. hypocrita. Therefore, urgent conservation measures are required to protect the Japanese bumblebees of the Nemuro Peninsula.

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Arabidopsis kamchatica subsp. kawasakiana [Brassicaceae] is an endangered winter annual that grows on sandy sea/lake shores in western Japan. In April 2006, we discovered a large population of the subspecies numbering more than 30,000 individuals on the eastern shore of Lake Biwa. At this site, plowing for beach volleyball games has been conducted every July since 2004. To gather information for the development of a conservation strategy, the plowing design used prior to 2006 was modified to create different schedules of plowing practices. Plant density and fruit production were measured during the following spring. One year of non-plowing, following two successive years of plowing, increased the number of individuals but had no effect on fruit production per unit area, as compared to sites that were plowed every year. Plowing prior to fruiting in June negatively affected individual density and fruit production. Our results indicated that plowing in July was the most effective practice for conserving the population. Plowing probably mimics past natural disturbances and accelerates the growth of the population by bringing the seed bank closer to the soil surface and by removing perennial competitors.

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We sought to determine the recovery potential of wetland plant communities from seed banks in abandoned dry rice fields. Vegetation was surveyed in three types of systems: abandoned rice fields, harvested rice fields cultivated from abandoned rice fields, and ponds that had once been wet rice fields. Seed banks were examined in abandoned rice fields using the seedling emergence method with three controlled water levels. During germination experiments with soils from harvested rice fields, we discovered the presence of a threatened species, Rotala pusilla Tulasne. This species was not observed in abandoned rice fields. We also found wetland plants such as Lindernia micrantha D. Don in harvested but not abandoned rice fields. In ponds that were abandoned wet rice fields, we found several threatened species, including Alisma canaliculatum A. Braun et C.D. Bouche ex Sam. var. azuminoense Kadono et Hamashima. Plants that grew before the rice fields were abandoned were recovered from the seed banks of abandoned rice fields using cultivation and water-level manipulation, two methods that promote plant growth. Our findings indicated that seed banks in abandoned rice fields are essential to the recovery of waterside vegetation. Therefore, the evaluation of seed banks during the development of abandoned rice fields is an important component of the recovery of plant communities.

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Occupancy is a widely used variable to describe spatial distributions of organisms. Although the statistic is easier to collect than other population indices, such as abundance, it often suffers from the problem of false absence arising when the detection rate of the target organisms is below 1. Imperfect detectability can cause serious bias in the estimation of relationships between occupancy and environmental factors and, thus, should be considered explicitly in the statistical model. In this paper, I present an introduction to a statistical model for species occupancy data with imperfect detectability using simple examples. Additionally, I explain appropriate survey strategies when imperfect detectability is inevitable.

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The channel catfish, Ictalurus punctatus, is an invasive alien species introduced from North America. We investigated the present status of the fish in Japan and found that it is widely distributed in the Abukuma, Tone, and Yahagi River systems, as well as in Lake Shimokotori. In 2008 and 2009, several channel catfish were also caught in Lake Hinuma and the Miya and Seta Rivers. We concluded that the distribution of channel catfish has rapidly expanded within natural rivers during the past several years. To avoid severe damage imposed by channel catfish to the river ecosystems and inland fisheries of Japan, risk assessments and examinations of the ecological characteristics and methods of capture of this fish species are urgently required.

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The history and present status of the conservation of Hibiscus hamabo Siebold et Zucc., which grows around salt marshes and is considered a semi-mangrove plant, were studied. Recently, several localities of this species have been designated as town, city, and prefectural natural monuments. The species is listed in the regional Red Data Book for most prefectures where it occurs. Citizens and government departments have performed numerous conservation activities. The conservation activities of citizens have varied, although some have incorrectly involved transplanting H. hamabo from other regions. It is important that conservation activities are carried out not only by citizens but also by government departments and researchers.

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