We investigated the effect of troop fission on home range use by Japanese macaques (Macaca fuscata) in Nikko, northern Japan, between March 1998 and October 1999. The home range of the macaques was determined by monitoring them by radio-tracking and direct observation. A troop before fission was designated as Sy, and daughter troops after fission were designated as Sy-1 and Sy-2. Our results showed that the Sy troop migrated seasonally, whereas Sy-1 and Sy-2 troops did not; the home range size per macaque increased on troop fission. The home range of daughter troops divided the home range of the troop before fission into half without range expansion. These results imply that after fission, troops can obtain the required food within their small home range without seasonal migration and that the food environment and social pressure from the neighboring troops affect such persistence. In general, troops of Japanese macaques in the wild are continuously distributed, and therefore, rapid expansion of the home range after troop fission seems to be rare in natural habitats.

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This study explores the potential demand for a bear-watching tour under consideration in Daisetsuzan National Park, Hokkaido, northern Japan, using choice experiment. The brown bear (Ursus arctos yesoensis) is representative of land mammals in Hokkaido. Local residents have overlooked to recognize bears as a potential tourist attraction; however, a bear-watching tour could provide benefit for local residents. Previous studies have shown that this kind of tour also improved wildlife management. A questionnaire survey was conducted in September 2008, and 302 responses (50.3%) were returned by mail. After removing respondents who were not interested in the tour, we analyzed the remaining 190 completed responses. Conditional logit model estimates demonstrate that the willingness-to-pay for the ideal tour, which is the best combination of tour destinations, group sizes, information services and probability of finding bears, is 8,804 JPY; thus, the tour would be profitable for the local residents. However, mixed logit model estimates show that hikers have heterogeneous preferences for tour destinations and information services. Therefore, varieties in terms of tour destination and information services are required to meet hikers' demands.

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We studied the feeding ecology of Great crested grebes Podiceps cristatus that were breeding in an irrigation pond; the study was performed during the chick-raising period. The grebes nearly exclusively exploited Stone morokos Pseudorasbora parva and Crucian carp Carassius gibelio langsdorfii and C. cuvieri. While the parents size-selectively used these fishes as food for the chicks, they also exploited seasonally abundant underyearling fishes. Consumable prey size was restricted for the youngest chicks, and the body depth of the fish was the restricting factor for consumption. Stone morokos were an important part of the diet for the youngest chicks, whereas Crucian carp became a more important food item at a later stage. Thus, our findings indicate that in the early stage of a brood, the important prey may be small fish with a low body depth, whereas larger fish with greater weight may become important prey at a later stage.

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Human dimensions of wildlife management is an academic field developed in the United States, and aims to provide the information that will improve the decision-making in the management process. Based on the idea and methods of human-dimensions studies, we conducted a survey to understand residents' behaviors and attitudes regarding Asiatic black bears Ursus thibetanus in Hyogo Prefecture. The objective of this study was to collect the data applicable for making policy recommendation to decrease the human-bear conflicts. Two thousand three hundred sixteen questionnaires were distributed to households in Tanto and Kami town which resulted in 1,209 responses (response rate = 52.2%). While the majority of residents in Kami town either reported sightings of bears or conducted interventions to prevent damage, only the minority in Tanto conducted such behaviors. Residents' preference of management responses (e.g., leave the bear, capture the bear, destroy the bear) varied when bears just appeared near the town, but became uniform when bears caused damages, mostly preferring to kill those bears. These findings can help wildlife managers understand the effect of previous outreach programs in fostering residents' behaviors, and set practical and measurable goals for the future planning.

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The Japanese hunter population has been declining and aging since the 1970s. As hunters' removal of nuisance animals is important for the prevention of agricultural damage, their retention is critical for sustainably managing Japan's wildlife. In order to understand the reasons for the decline in the number of hunters and propose appropriate retention measures, we surveyed 1,409 people who did not renew their hunting licenses in 2008 and 2009. The respondents who revoked their trap hunting licenses were younger and had significantly shorter hunting careers than those who revoked their gun hunting licenses. The former had mostly carried on hunting for nuisance control until the cost of hunting became too expensive for them to continue. Therefore, provision of economic incentives could be an important retention measure. While the main reason given by both big game and bird hunters was the reinforcement of gun holding regulations, bird hunters indicated that the reduction in the number of game birds and loss of hunting area were also problematic factors. Thus, in order to retain bird hunters, it is important to improve the environmental conditions of bird hunting.

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We investigated fish fauna in the littoral areas of Lake Saiko and Shojiko, Yamanashi Prefecture, Central Japan and compared them with those in previous studies. Two species have newly appeared in each lake: Oncorhynchus masou masou (Salmonidae) and Pseudogobio esocinus esocinus (Cyprinidae) in Lake Saiko and two Gobiidae species, Tridentiger brevispinis and Gymnogobius urotaenia, in Lake Shojiko. Three of these fishes are non-indigenous Japanese fishes and may have been introduced unintentionally in recent years, whereas O. masou masou was stocked for fishing by fishery managers of Lake Saiko. In Lake Saiko, the fish species composition has greatly changed and a goby, Rhinogobius sp. OR, has been dominated by another goby, T. brevispinis, during the past decade. In Lake Shojiko, species composition and dominant species has not changed and a goby, R. sp. OR, was the dominant benthic fish in littoral areas. However, we found that T. brevispinis has also invaded Lake Shojiko recently and greatly increased in number during the study period. The results indicated that unintentional introduction of non-indigenous fish species may have frequently occurred with fish stocking in recent years.

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This study elucidates local residents' opinions on the release of the Japanese crested ibis (Nipponia nippon) on September 25, 2008. Questionnaire surveys were conducted by mail twice in Sado City, Niigata Prefecture, on August 2008 (before the release) and in January 2009 (after the release), to assess the extent of awareness among local inhabitants. Of the 1000 randomly selected inhabitants aged 20-79 years, 567 and 591 responses were obtained for the first and second surveys, respectively. The majority of respondents regarded the release favorably primarily because "The birds are indigenous to the area"; however, very few of the respondents had seen Japanese crested ibis in the natural environment. Comparing the responses from the two surveys revealed an increase in the number of inhabitants that regarded the presence of the crested ibis favorably. In addition, more people regarded the crested ibis as a local symbol and fewer inhabitants regarded it as a threat to their agricultural activities. In a similar survey for the white storks (Ciconia boyciana), the release was regarded favorably because "The birds are indigenous to the area." These findings suggest that local inhabitants are more open to the release of birds in an area if the birds are indigenous to that area.

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