I detected the lag-phase in population dynamics of sika deer (Cervus nippon) and raccoon (Procyon lotor) populations in Chiba Prefecture based on spatiotemporal changes in sex ratio of culled animals. I examined a method to catch raccoons under low density using data from the Raccoon Removal Program in Inzai-City, Chiba. In some sika deer and raccoon populations, high male/both sex ratios suggested that they were under a lag-phase with an Allee-effect in low density areas, at the edge of the distribution and within a heavy culling area. Accordingly, I propose “lag-phase management,” with the goal of achieving and maintaining populations in a lag phase, which is detectable based on the male/both sex ratio, etc., preceding whole eradication or local removal.

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We surveyed the habitat use of the Japanese squirrel, Sciurus lis, in a patchy woodland landscape to examine the effects of ecological factors such as vegetation, patch size, and connectivity on the Isawa Alluvial Fan in southwestern Iwate Prefecture. Field signs of the squirrel were found in 109 of 177 forest patches. We examined ten factors to determine the habitat of the squirrel: presence of walnut trees, presence of red pine trees, forest patch size, area of deciduous broadleaf forest within a forest patch, distance to the nearest forest patch, distance to nearest large forest patch (>10 ha), percentage of paddy field, dry field and developed area, and road length per hectare within a buffer surrounding the forest patch. Nine of these variables except percentage of developed area within buffer had significant correlations with habitat use or non-use by the squirrel. We used logistic regression to develop models to predict the use or non-use of forest patches by squirrels. In the best model, two variables were selected: presence of walnut trees, and area of deciduous broadleaf forest within forest patch, in order of importance. An additional field survey to validate the model showed a prediction accuracy rate of 75.9%.

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Between 18th October and 7th November 2010, three raccoon dogs were captured in Field Museum Tamakyuryo (FMT), and behaviour at fences was recorded by IP cameras at an enclosure. In this enclosure, fencing constructed of diamond-mesh wire netting, 150 cm in height, was used in conjunction with two types of mitigation commonly used in highway fences to prevent raccoon dogs from climbing (PVC board, Trical net). The raccoon dogs escaped successfully by both digging under (adult male) and climbing over the wire fence (yearling), but were not able to climb over the Trical net. Attempts to circumvent the mitigation treatments included biting, stretching the forelegs and/or stretching the nose upwards with standing on rear legs and pawing at the fence. Between October 2011 and October 2012, seven wild raccoon dogs were captured and measured at the TUAT campus, FMT, and Hinode town. These had a minimum paw width of 27 mm, indicating the largest fence mesh size capable of preventing them from climbing the fence. Their minimum lower jaw and canine width was, however, 12.4 mm, and therefore they were able to bite onto even this small Trical net mesh size of. Thus, maximum Trical net mesh size appears to be within 12.4 mm for purpose of bite-proof by raccoon dogs. The maximum gap between the forelegs was 53.6 cm, therefore PVC prevention board larger than this should not be scalable by raccoon dogs.

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To analyze the food habits of the wild boar (Sus scrofa), we collected stomach contents from 294 wild boars from Iwami District, Shimane Prefecture, western Japan, between April 1998 and March 1999. The frequency of occurrence and the proportion of each food item in the contents were analyzed using the point-frame method. Vegetable matter, which was categorized into bamboos, dicotyledons, tubers, plant fibers, and acorns, occurred more frequently in their diet than animal matter, and also constituted the bulk of the food ingested. Wild boars mainly ate bamboos (mean proportion in total stomach content, 57.9%) in season I (May–June), dicotyledons (27.6%) in season II (July–September), tubers (43.3%) in season III (October–December), and plant fibers (30.3%) in season IV (January–March). Wild boars also ate acorns from season III to IV (20.0% and 20.4%, respectively). Compared with other wild boar populations, the wild boars in our study had a stronger tendency to eat the underground parts of plants consistently throughout the year, except during summer.

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Two invasive lineages of Black Rat (the Rattus rattus species complex) occur in Japan: the newly introduced Rattus rattus (2n=38) of Indian and European origin, and the anciently introduced R. tanezumi (2n=42) of East Asian origin. To assess the current distribution and invasion history of these lineages, we determined the nucleotide sequences of a coat color-related gene, melanocortin 1 receptor (Mc1r, 954 bp), in 36 rats from Japan and conducted phylogenetic analyses for a total of 133 rats mainly from Japan (17 localities). Mc1r haplotypes representing R. rattus were recovered from Otaru, the Ogasawara Islands, and Tokyo, and heterozygous individuals with the R. tanezumi type sequences were detected in these localities. These results imply that introgressive hybridization is currently going on in a variety of places in Japan such as urban and port areas, and on remote islands. In contrast, the R. rattus haplotypes were not detected in the natural forests of the Ryukyu Islands here represented by the islands of Amamioshima and Okinawa, implying the presence of some mechanism preventing the introduction of the invading lineage. We recovered some endemic haplotypes from the Ryukyu Islands, suggesting genetic differentiation between the Ryukyu Islands and other parts of Japan.

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We analyzed factors affecting the road-kill frequency of red fox, Vulpes vulpes, including landscape structure around the roads, and harvest of sika deer, Cervus nippon yesoensis, for nuisance control and hunting in eastern Hokkaido, Japan. Generalized linear models explaining the road-kill frequency of red fox in each 2 km transect were generated for the birth and pup-rearing period, and for the dispersal and breeding period, using road-kill data for 2000 and 2009 on national roads. Model selection revealed that the road-kill frequency during birth and pup-rearing period increased with increasing proportion of grassland area and the number of deer harvested for hunting within a 1 km radius of the center of the transect. The road-kill frequency during the dispersal and breeding period was associated with landscape diversity index positively, and with deer density index negatively around the transect. These results suggest that important factors affecting red fox road-kill frequency differed between the two periods. We also suggest possible effects on red fox of landscape diversity, utilization of shot deer carcasses, and indirect effects of deer.

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We estimated the population size of Martes melampus from faecal DNA in Aso District in Kumamoto Prefecture and Saga City in Saga Prefecture, Kyusyu, Japan. From analysis of DNA extracted from faeces, 95 individuals were identified in Aso, while 50 were identified in Saga, among which 13 in Aso and 10 in Saga were considered resident. We calculated the population size per hectare as 0.14 to 0.19 in Aso and 0.09 to 0.13 in Saga. These estimated densities were very high compared to previously published studies on Martes. There were some cases in which mature individuals of the same sex that were not blood relatives had overlapping ranges, indicating that these animals were not always exclusive.

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We captured sika deer (Cervus nippon) via catch-and-kill methods including driven-deer shooting; large-enclosure traps (S); stalking and shooting; sharp-shooting (SS), and methods for chemical immobilization and euthanasia or release, i.e. mobile-enclosure traps (alpine); large-enclosure traps (E); free-range ambush and shooting. Creatine kinase (CK) was measured as a physical stress index, and epinephrine and norepinephrine were measured as indices of stimulation of sympathetic neurons. CK, epinephrine, and norepinephrine were significantly higher when driven-deer shooting than when other methods were used (except in the case of the CK in SS) (P<0.05). Cortisol, which was measured as an index of mental stress, tended to be higher in enclosure traps (alpine and large enclosure traps (S, E)) than with other methods but were within normal limits for red deer (Cervus elaphus) (Gaspar-López et al., 2010). These results suggest that driven-deer shooting subjects them to strong physical stress, and that the mental stress imposed by enclosure traps is not excessive. Thus, reducing deer populations via enclosure traps is a more appropriate initial method of population management in terms of animal welfare considerations.

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The use of dead-leaf foliage as day-roosts by the Ryukyu tube-nosed bat, Murina ryukyuana, was first recorded under natural conditions in subtropical broad-leaved forest on Tokunoshima Island, Japan. Three tree species were found to be used by the bat as day-roosts: Idesia polycarpa, Symplocos cochinchinensis, and Schefflera heptaphylla. These three tree species appeared to share common traits, being relatively broad-leaved and forming foliage under dry conditions. The Ryukyu tube-nosed bat might use various types of roosts as well as dead-leaf foliage, since the use of varied roosting sites has been documented in other Murina species, including tree cavities, under bark, dead-leaf foliage, leaf litter, and caves. Accumulating information through incidental observations and radiotelemetry tracking could lead to a better understanding of the roosting ecology of this species.

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The Amami spiny rat (Tokudaia osimensis), is an endangered species endemic to Amami Oshima Island, which is a part of the Ryukyu Archipelago in Japan and expresses an XO sex-determination system. Captive breeding must be used to help conserve this species. Here, we tried long term rearing in the laboratory with a similar condition for conventional experimental animals such as mice (Mus musculus) and rats (Rattus norvegicus). In this study, although we could not achieve breeding, we succeeded in rearing more than four years (1,459.8434.3 days) for six out of seven Amami spiny rats introduced into our laboratory with the following conditions: room temperature 232°C, humidity 5010%, 12H dark and 12H light periods. We used conventional cages, drinking bottles, woodchips, shredded paper for nest material, and normal experimental animal chow used for mice and rats. Judging from their weight gain, food intake, and faecal apparent digestibility, the experimental animal chow was a prefered food item for the Amami spiny rats. However, the thermoneutral zone for this species was estimated as more than 26°C. We suggest that successful in captive breeding of this endangered species requires particular attention to the appropriate room temperature.

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Although pastures are often good feeding sites and can benefit deer population growth, the pasture utilization of sika deer (Cervus nippon yakushimae) in Yakushima Island is not clear. Spotlight counts of deer were conducted in the Nagamine pasture on Yakushima Island every month between 2006 and 2009. Mean deer density utilizing the pasture was estimated to be 420 deer/km². Deer density in the pasture decreased when spotlight counts were conducted soon after sunset and pasture land was dug up, which may result from higher disturbance by human activity and lower abundance of pasture plants. In contrast to other reports in northern Japan, seasonal variation of pasture utilization by deer was not detected. This may be due to relatively constant quality and quantity of deer forage in the evergreen broad-leaved forests on Yakushima Island. Since 2010, the immediate surroundings Nagamine pasture have changed drastically, and it is therefore important to continue monitoring deer densities in and around the pasture.

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There has so far been no record of the frosted Myotis, Myotis pruinosus in Kumamoto Prefecture. We confirmed their inhabitation by capturing these bats at their tunnels in Yamato-machi, Kumamoto Prefecture on 30 September 2007, 27 July and 24 August 2008, and on 27 November 2011. In some bats, the fur was not blackish but dark or grayish brown, and the tips of the guard hairs on the back had no silver metallic luster, unlike those of M. pruinosus. However, the plagiopatagium of the bats was inserted in the base of the first toe, unlike in M. macrodactylus. The bat’s blood vessels formed a straight line in the tail membrane, while those of the closely related M. ikonnikovi formed a curve. Therefore, we identified them as M. pruinosus. This was supported by phylogenetic analysis based on the mitochondrial gene (Cyt b) sequences, and genetic and geographical variations were suggested in this species. Forearm and tibia lengths in Kyushu were significantly larger than those in Honshu and Shikoku. In the skull characters in Kyushu, CBL was short, and ZW and BCW were large as compared with those in Honshu and Shikoku. These results were further supported by principal component analysis.

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About two and a half years have passed since the Great East Japan Earthquake on March 11 2011. Some research on the accumulation and effects of radionuclide in wild animals released from the Fukushima Daiichi Nuclear Plant has been progressing since then, but the actual condition and management of wildlife on the whole are inadequate in many cases mainly because of strongly limited human activity especially in the evacuation area. Some changes in behavior have been recognized in Japanese macaques Macaca fuscata as probably due to changes in farming conditions and the associated impact on food due to radioactive contamination in the high-dose area, in the evacuation area in Fukushima Prefecture. And concentrations of radiocesium in two macaques captured in the high-dose area were very high. On the other hand, macaques captured in a middle-dose area, Fukushima City, showed very high values especially in the accident year, and a decline of white blood cells was also observed. In large hunting animals, even in the low-dose area of Fukushima Prefecture and other peripheral prefectures, individuals that have more than the regulation value in food (100 Bq/kg) were present. In addition, because of high dosage in the evacuation area, the management of wild animals has been become difficult, and changes in home range and population increase of wildlife species have been documented there as well as in the low-dose area. Conflict with humans due to population increase via decreased hunting activity has occurred. Recently, the legal treatment of radionuclides in the environment has changed to as the same status as pollutants under the new “Revised Basic Environment Law” since 2012. However, only rodents were selected from mammal species as the 26 species of the standard flora and fauna for environmental impact assessment by the Ministry of the Environment. And the monitoring area is within a 20 km distance of the Nuclear Plant. Therefore, we propose here that macaques and large-sized hunting mammals, such as boar Sus scrofa and sika deer Cervus nippon, should be added to monitored species in the standard flora and fauna for environmental impact assessment. A monitoring method should be applied that is unified and intentional not only in the evacuation area but also in the low-dose area. Standardization and sharing of assessment methods and evaluation methods of radionuclide activity effect should be attempted. Conservation and management measures of wild mammals, the sharing of information among local, and rapid release of outcome information to domestic and international are required.

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