Ectoparasitic organisms have specific traits biologically adapted to their natural hosts to acquire an environment and food necessary for their survival. It is disadvantageous for them to infect non-host animals. Previous studies have shown that a bat Miniopterus fuliginous is the only natural host for a bat fly Penicillidia jenynsii. Therefore it is possible that P. jenynsii has some mechanism to discern M. fuliginous from and/or avoid other bat species. However no research has been conducted to examine such a mechanism. In the present study, pieces of fur cut from M. fuliginous, M. macrodactylus, the Japanese large-footed bat, and R. ferrumequinum, a greater horseshoe bat, all of which inhabit caves and occasionally rest together in the same cave, were prepared, and behavior of P. jenynsii was examined. The results showed that P. jenynsii tried to burrow into the fur pieces of M. fuliginous much more eagerly than into those of the other bat species.

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On August 4, 2006, an official photochemical smog alert was issued to five prefectures in the Tokyo metropolitan area and further to Fukushima Prefecture. The highest O₃ level that day was 157 ppb, which was recorded in Ibaraki Prefecture and Saitama Prefecture. The highest value was recorded in Gunma Prefecture at 17:00, suggesting possible of advection of the pollution. In addition, analysis of mean-sea-level barometric pressures revealed that, heat lows occurred in Nagano Prefecture and Fukushima Prefecture. Furthermore, heat lows were typical central Japan on clear summer days.

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Environmental conditions of egg deposition sites of wild minami-medaka Oryzias latipes were investigated in an aquatic area of a biotope in order to obtain basic information for conservation of wild Japanese medaka species in danger of disappearing. Deposited eggs were observed mainly at the banks of shallow streams where the flow rate was below 1cm/sec. Eggs were also observed in the fallow paddy field. Few eggs were observed in the deep streams and the ponds. Eggs were mostly deposited on relatives of Genus Spirogyra, fresh water algae, as a substrate. The deposition sites were situated at the depth of 0 to 15 cm in water.

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