Chronological and geographical variations of the Late Pleistocene/Holocene Japanese macaques (Macaca fuscata) were examined on the basis of molar measurements between modern and fossil specimens. The fossil specimens were collected from late Pleistocene and early Holocene localities in Japan, and they were compared with modern specimens. Dividing the modern specimens into eastern and western phylogeographical groups around 134°E boundary suggested by genetic studies, the mean of the molar size in the western (Chugoku and Kyushu) group was significantly smaller than that in the eastern, although their variations are not correlated to geographical cline. Most late Pleistocene specimens in Honshu have buccolingually wider molars, and also the Holocene specimens from Gongendani-no-choana Cave in Kinki District and Tanegashima Is. have similar characteristics. On the other hand, the Holocene specimens in Chugoku and Kyushu District are slightly smaller than the other fossil specimens, as large as the modern western group. These results suggest that there was a decreasing molar size during the latest Pleistocene to early Holocene in Chugoku and/or Kyushu District. Consequently, we infer that the appearance of the molar size variation between eastern and western Japan is relevant to the phylogeographical pattern reported via patterns in genetics.

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We used fecal analysis to investigate the food habits of wintering sika deer (Cervus nippon yesoensis) in relation to snow depth in western Hokkaido, Japan, during the winters of 2006–2007 and 2007–2008. The snow depth in the wintering area exceeded 100 cm for more than two months in both 2006–2007 and 2007–2008, and the maximum snow depth was 152 cm in January, 2008. In periods without snow cover, feces contained graminoids, Sasa senanensis, dicots, and many food plants. In snowfall periods, fecal contents were dominated by S. senanensis and arboreous plants (bark and twigs). When snow depth exceeded 100 cm in mid-winter, S. senanensis was unavailable because of snow cover, and arboreous plants dominated fecal contents. These results show that snow depth strongly influenced the food habits of sika deer in heavy snow areas. S. senanensis and arboreous plants were important food resources during winter, and deer depended on arboreous plants when snow covered S. senanensis.

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Invasion of non-native species causes detrimental impacts to biodiversity, ecosystem function, and human economies. To reverse these impacts, invasive species are often removed by trapping, shooting, poisoning, and other such methods. Growing evidence suggests that reducing invasive species can lead to successful ecosystem recovery. However, degraded ecosystems sometimes fail to recover, and reduction of invasive species sometimes result in even more harmful impacts. These unintended phenomena are increasingly recognized; however, few attempts have been made to integrate scattered information on solutions. In this review, I explore several possible situations that can cause unintended consequences, including environmental dependency, nonlinearity, hysteresis, and interactions among invasives, and relate these to processes such as switching, Allee effects, synergistic relations in both invasions and habitat modifications, mesopredator release, and so on. Additionally, I list management actions associated with each process, such as assessment of ecosystem recovery, habitat management, and management of other species. Practices mitigating unintended consequences using these actions are increasingly reported. Compiling the results of these trials would contribute not only to solving local problems, but also to guiding and facilitating further case studies.

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A bat found in Teine, Sapporo, Hokkaido (43°07′N, 141°11′E) on 9 November 2007 was identified as Hypsugo alaschanicus (Bobrinskii, 1926) from morphological data. This is the fourth capture in Sapporo, and the eighth in Japan. The skull of this specimen was compared with those of other five specimens of H. alaschanicus previously recorded in Japan. The occasional absence of anterior upper premolars, which was previously pointed out, was confirmed. In comparison with Eptesicus nilssonii, the direction of the upper canine cusp and the ratio of the height of the lower canine to that of the posterior premolar were newly found useful as additional morphological characters to identify both species.

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Two types of traps, box and bag-types, were newly designed for the live capture of the Kuril harbour seal, Phoca vitulina stejnegeri. The box-type trap was designed based on the traps used by the Nivkhs, the former inhabitants of Sakhalin, for catching the spotted seal, Phoca largha, and the bag-type based on the traps used by local fishermen to commercially harvest Kuril harbour seals in Akkeshi Bay, eastern Hokkaido, Japan. Three adult Kuril harbour seals were successfully captured alive in 2009 in Akkeshi during a period of about 30 days in a total of 3 sets of traps. The box-trap has the advantages over the bag-trap of higher catch efficiency (seal catches per open trap day), lower risk to seals, easier handlings of animals including anesthesia, lower cost etc.

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The purpose of this study was to clarify annual changes and seasonal differences in sika deer population density in the Tanzawa mountains. We investigated population density via the block-count method in spring and winter from December, 1998 to April, 2007. In the study area, artificial feeding was carried out in winter 2001.
Population density did not appear to change in winter and spring. On the other hand, spring population density was lower than that of winter in non-artificial feeding periods.
Population density did not decrease even when food condition was poor in the study area. This is probably due to the deer using new foods like fallen leaves, and a lack of heavy snowfall.
The reason for the population density depression in spring may be the migration of the deer from the wildlife protection area to the game area in the non-hunting season, and higher mortality in winter.

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Thirty Japanese badgers (Meles anakuma) were collected in Gunma Prefecture from 1999 to 2010, and their pancreases were examined. Of the total, 96.7% of the badgers were infected with Tetragomphius melis. Intensity of T. melis ranged from 3 to 266. Nodular and tubercular lesions were formed around the pancreatic duct. The size of tubercles ranged from 1.0 cm to 6.8 cm. In spite of the large tubercles or heavy infection of the nematodes, infected badgers were in good shape and showed no evidence of disorder in function.

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Tree cavities appear to be important nest resources for Japanese flying squirrels, Pteromys momonga. The purpose of this study was to clarify the status of the use of tree cavities in Cryptomeria japonica and Chamaecyparis obtusa by Japanese flying squirrels. We located research sites for the nesting of Japanese flying squirrels in a patchily mixed forest consisting of coniferous plantations, C. japonica and C. obtusa, and broad-leaved tree woods in the Tanzawa Mountains, Kanagawa Prefecture. From March 2005 to April 2010, nest sites of Japanese flying squirrels were confirmed in only 1 of 20 broad-leaved trees, and in 8 of 23 conifers (21 trees of Cryptomeria japonica and 2 trees of Chamaecyparis obtusa), showing that conifers were significantly more nested than broad-leaved trees and the coniferous trees nested were all Cryptomeria japonica. In all conifers with nests, the measurements of the tree height, the diameter at breast height and the cavity height were 25.6±3.7 (mean±SD) m, 50.3±11.2 cm and 6.2±0.6 m, respectively. On the other hand, in all the conifers without nests, these measurements were 27.3±1.2 m, 45.5±9.3 cm and 7.5±0.6 m, and these three variables did not differ significantly between the trees with and without nests.

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This paper describes capture and handling methods of northern fur seals (Callorhinus ursinus) on land and at sea for scientific research and for proper treatment of individuals stranded or caught incidentally in fisheries. Females and smaller males (c.a. <70 kg in body weight) can be caught on land by using a noose pole or a hoop net, and physically immobilized with a restraint board. Handling of large males requires chemical immobilization. Careful attention should be paid to the respiratory condition of animals during capture and immobilization. On breeding lands where northern fur seals form dense social aggregation, proper methods of approach, capture and restraint should be chosen to minimize disturbance to the breeding aggregation and to ensure the safety of animals and field workers. Captured animals should be returned safely to the original location so that they can retain social relationships with other individuals. Live capture of northern fur seals at sea is possible using gillnets in foraging areas. Since capture and possession of northern fur seals are restricted by Japanese domestic law, government permission is required to capture northern fur seals for scientific research.

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Careful management is necessary for two bear species, the brown bear (Ursus arctos) and the Asiatic black bear (U. thibetanus), as game animals in Japan. We reviewed the population size estimations and population trends of these bears for their management planning and implementation. Several methods, such as questionnaires on status, harvest statistics, demographic indicator analysis, direct count, capture-mark-recapture, camera trap, field sign and hair trapping, have been applied for estimating population sizes of the bears. The bear harvest can be more influenced by environmental fluctuations such as mast production and management policies than actual population fluctuation. Snow cover and other field conditions may influence the direct count method. The field sign method can be used for population trend studies, but not for absolute population estimation. Six prefectural governments of 17 which have made bear management plans for specific wildlife management system have applied the hair trap method, which has been developed in recent years, for the census of the Asiatic black bears. The entire estimated population of the Asiatic black bear based on local government reports was 13,169 to 20,864, including the process of extrapolation to the entire range in Japan. A study on the reliability of estimated population size methods is requested through further monitoring of the bears by central and local governments.

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We collected one specimen of Apodemus speciosus with small eyes suggestive of a microphthalmia-like aberration in Fujisawa, Kanagawa Pref., Japan. The external appearance and skull characteristics of this specimen were normal except for the eyes. We observed under the microscope that there was a small lens-like tissue and soft tissue in the internal status of the eye. In contrast, a normal specimen’s eyes were filled internally with lens. Thus, these small eyes were recognized as an aberration, for example a microphthalmia mutation, indicating the first record of such an aberration in A. speciosus collected in the field.

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