To estimation the growth pattern of Japanese wild mouse (Mus musculus molossinus) in a laboratory colony, body weight data were fitted to Richards growth model. Usefulnes of "three point method" was also investigated. To select the three point messurement values, the entire measurement period was divided into initial,middle and final periods,and three values were extracted from a measurement during each period. Three were set ap as nine types of combinations. The shape parameter"m"in the growth model was set from 0 to 2.0 at intervals of O.J.The fitness of the estimation was assessed by the determination coefficient (R^2 value). 1) The growth model was estimated with 98% or greater of R,indicating that"three point method"seemed to be effective for estimating the Richards growth model. 2) The shape parameter"m" at the highest R value was presented at 0.0 in both sexes and growth carve of Japanese wild mouse had no inflectional point (monomolecular curve). 3) The relation between "m" and R^2 was able to be shown with a curve that"m" is a definit curve.

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The well-known method INTGEP was applied to the estimation of population size of hare in a mountainous area, 18,750ha, of Fukushima Prefecture. Besides the tracks of hares, those of fox, racoon-dog and Japanese sable were counted. The population density of hare was estimated to be 0.11 (0.09) per ha, the mean length of tracks of hare being assumed tobe 1200 meters (1500 meters). The relation between the density of track of hare and natural environment is also discussed by Quantification Method II.

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[in Japanese]

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The authors investigated five injury incidents and one death incident of humans due to attacks by brown bears (Ursus arctos)during hibernation , occurring in Hokkaido Japan during the 26 years from 1970 through to 1995. Details and characteristics of these bear attack incidents and countermeasures to prevent attacks and injury are described within. The reason bears attack while they are hibernating is to protect their den from possible human intrusion. If they scene a possible threat close to their den they will leave their den to drive off the perceived threat. A hibernation den is a tunnal cave dug by bears in a mountain slope. Bears in Hokkaido usually start hibernating from late November to late December and finish hibernating from late March to early May. It has been observed that in general dens with a larger than average entrance have been a feature in relation to attacks on humans. In the one reported case of a human death due to a bear attack in Hokkaido, occurred in early December very early in the bears hibernation. The bear stood up and attacked with its hand claws. All other reported attacks did not lead to death. These attacks all occurred after late February. This is past the half way point of the bears hibernation. The bears had used up so much energy in keeping warm during winter the bears therefore did not have enough energy to stand up and attack. They attacked their human victims only with their teeth. Therefore it appears in order to minimize injury from bear attacks. It is better to start work in bears hibernating areas after late February, which is past the half way term point of hibernation. Bears usually don't have enough energy to stand up and attack past the half way point of their hibernation. Standard safety measures to help prevent bear attacks on humans, people shoud carry a sound-making instrument, such as a whistle or a bell, and a hatchet(a big knife) for self-protection when entering an area presumed to be a bears habitat. While walking, people should blow or rattle the sound-making instrument, or raise their voices in order to avoid encountering bears unexpectedly. Because bears dislike hibernating in a place where the environment has been artificially changed, minor modifications to the environment are effective in preventing bears from making dens. Bears lurking obstinately in their den should not be killed. People can safely work around a bear's den if they remain 50 to 100 m away from it. Bears often use several different dens. Therefore, bears escaping from a den due to the intrusion of humans usually enter another den, and it is not necessary to chase and kill them. When encountering a bear people should never run to escape or feign death as the bear is sure to attack. The best actions are to stand, be confident and shout at the bear in a loud voice. Such actions are often successful and the bear will leave. If a bear should actually attack the best response is to deliver a blow of a hatchet on any part of the bears body. This will increase the chance of survival.

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Since 1983 Hazel Grouses (Tetrastes bonasia) have been reared and kept in captivity for use in studies on biology and captive breeding in the Obihiro University and Veterinary Medicine, Hokkaido. Birds fed on the basic diets (a mixture of commercial poultry rations, pet food and fish meal with vegetables; in addition, mush for quail, commercial chick feed and boiled yolk were added for chicks) showed similar growth and seasonal changes in body weight in natural conditions. However, there are some problems connected with the reproducing eggs and rearing birds; 1) difficulty in collection eggs in the field, 2) birds bred by artificial incubation and rearing do not show escape behaviour from peoples, 3) although rearing chicks by mother bird is better than artificial rearing, large aviary is required for the former method of rearing, 4) gizzard developed poorly in birds fed on artificial diets compared with wild birds, 5) careful management of aviary is required to prevent disease such as aspergillosis. In addition, assessment of habitat conditions such as food conditions, hiding places and nest sites before releasing birds. The growth of the Hazel Grouse populations is not expected by releasing bird bred in captivity and habitat improvement is the important procedure to maintain the population level in Hokkaido.

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One of the important problems in the world is how human being coexists with nature. The global view point is desirable for this problem, and Japanese sense and attitude or view of nature is to be taken into consideration. We performed a nation-wide survey on view of nature in 1993, based on the result of pre-test for students. In this paper, we discuss some topics from the results. First we take up the way of thinking about relation between man and forest. The opinion that nature preservation is more important than people's well living and the primitive religious feeling to nature are shown to be close concept, and feeling of confidence in human relations is very close to the primitive feeling too. The attitude structure toward them is different from the German. The second important point is on the way of thinking about relation between man and wild animals. The livings things which have to be protected from extinction are partial to those people feel good, for example, prety, usuful and so on. Further,the younger people who have few experience of concern with wild animals have the opinion that nature is important and wild animals have to be defended. The last interesting point is to learn the list of wild animals living in Japan which the respondents know and their familiar trees. We can find that the listed names are different, depending on the areas of the respondents. This fact suggests that people receive the influence of the natural environment in consideration of some problems about man and nature.

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