Masked palm civets (Paguma larvata) not only cause agricultural damage but also invade houses in Japan. To prevent damage to houses, in previous studies we investigated the sizes and shapes of gaps large enough for masked palm civets to enter. However, the long side of the rectangular gaps was fixed to 20cm, although civets might be able to enter smaller rectangular gaps. In this study, we researched the sizes of rectangular gaps large enough for civets to enter by reducing the short and long sides of rectangular gaps in 1cm decrements whenever a civet successfully entered them. In addition, we investigated their exploratory behavior in front of the gaps and how they entered the gaps to consider the invasion strategy. The minimum sizes of gaps that civets could enter were the H6×W12cm horizontally long rectangle and H11×W7cm vertically long rectangle. Exploration of gaps included not only olfactory and optical contacts, but also physical contact such as insertion of the muzzle into gaps. The time spent smelling and muzzle insertion into the gaps showed significant differences between the maximum sizes of gaps entered (Max), minimum sizes of gaps entered (Min), and gaps failed to enter (FE), and these time were the longest in FE (respectively P<0.01). However, the time spent on gazing in front of each gaps showed no significant difference. These suggest that civets did not decide whether to enter from the gaps using only visual information, they also decide from smelling and inserting the muzzle into the gaps and trying to enter them.

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Since dogs are used for a wide variety of purposes by humans, it is very important to acquire knowledge about their perceptual and learning abilities. In this study, four dogs (Canis familiaris) were trained to "O-I-De ("come" in English)" and "Ha-U-Su ("house" in English) reliably response to recorded commands. The experimenter (trainer) sat on a chair to restrict body movements, wore black glasses to eliminate eye contact with the dog, and used recorded verbal commands presented via an equipment. Performance was low in all cases compared with the true command condition. The response score to the change of the consonant of command "O-I-De" has decreased compared with the true command. In addition, it was significantly slow at time from the presentation of the command to the completion of the response compared with the true command. A response score of command "Ha-U-Su" showed similar to "O-I-De" a tendency. Moreover, response time was compared with the true command and the consonant change command was slow. The results suggest that dogs might recognise a slight change in a Japanese command of three phonemes as well as the results of English commands.

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We conducted palatability tests with 11 captive sika deer (Cervus nippon; hereafter, deer) to search for optimum baits to attract and capture wild deer at pasture in Experiment 1. The tests were conducted using grasses and baits with which captive deer have no feeding experiments. In Experiment 2, to investigate the attractiveness of these baits, we set the top two palatable baits identified in Experiment 1 at feeders placed in a pasture where many wild deer had been observed. The top two palatable baits preferred by the 11 captive deer in Experiment 1 were a formula feed that contained molasses and corn, and flaked corn. In Experiment 2, in fact, 96% of the animals attracted by the baits were two species of crows and 3.8% were raccoon dogs, whereas, wild deer comprised only 0.2%. Baits used in this study were also attractive to nontarget animals. This suggested that these baits reduce capture success by attracting nontarget animals and are not appropriate for attracting and capturing wild deer at pasture where there is a lot of wildlife. Further studies are needed to identify the attractive bait for wild deer with taking into consideration the disturbance by nontarget animals.

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