In and around the Kujo Agricultural Research Center of Kyushu University at kuju Highland, field studies on the distribution and seasonal fluctuation in the number of Haemaphysalis longicornis, and on the fauna of small mammals and their ectoparasites, and also a survey on the avifauna were carried out together with laboratory experiments on the cattle tick. The results are summarized as follows: 1. Ecology of H. longicornis a) All the ticks collected either by dragging a flannel cloth over pasture or directly from grazing cattle were identified as H. longicornis. iin the examination on O pasture in midsummer (middle in July), all stages (larva, nymph and adult) of H. longicormis were involved. On the other hand, in the early autumn (late in September) no adult tick and few unfed nymphs were collected, but unfed larva showed a remarkable increase in its number. b) The unfed adult ticks collected on O pasture in midsummer consisted of 22 males and 17 females, and 13 partly engorged adult ticks got at random from the cattle were females. There was ma marked positive correlation between the total number of deposited eggs and the body weight of female, i.e., the former increased in proportion to the amount of sucked blood. The number of laid eggs per 1mg of the body weight of partly engorged adult females averaged 10.9, and it increased at a high temperature of 29.0℃ on the average. All of the adult females lived a mean of three days after oviposition. c) The duration of the egg stage was markedly shortened with the rise of temperature, and the mean daily accumulative temperature and the mean developmental zero occupied for incubation was 357 day-degrees and 10.7℃, respectively. Although the developmental velocity of tick egg varied according to temperature (22.1℃, 24.9℃ and 28.6℃ on the average), there was little variation in the hatch-rate (81.1～82.9%). d) The body weight of newly hatched larval ticks averaged 0.038mg and the largae became active about one week after hatch. e) The period required for engorgement of the larval ticks averaged six days, during which period the mean body weight of the engorged larvae increased about 12 times (0.450mg) of the seed tick. The molting period was 23 and 10 days at mean temperatures of 25.1℃ and 28.2℃, respectively. 2. Small mammal fauna and the ectoparasites a) From the small mamals (three species of murid rodents and two species of insectivores) captured in July and September, 15 species of ectoparasitic mites and one species of tick were recovered. Nine out of 14 species of the ectoparasites from the murid rodents belonged to Laelaptidae. no H. logicornis was found at all, whereas a single engorged larva of Ixodes ovatus was taken from the ear flap of the Japanese field mouse, Apodemus speciosus. b) In the infestation experiment in the laboratory, it was confirmed that the larval H. longicornis infests not only the guinea pig, Cavia porcellus, but also the japanese field vole, Microtus montebelli, and molts to nymphal stage after engorgement. 3. Avifauna and the ectoparasites All birds (31 species) observed excepet a few species were ground-frequenting birds. As it seems highly possible that many kinds of ticks and mites may infest these birds while they feed mostly on the ground, a detailed investigation on their role and significance as a carrier and/or a host of the ectoparasites is desirable in and around the Center in the near future.
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