A biotope, with an area of 1500 m^2 and consisting of ponds and water canals, was constructed in the experimental field of Koibuchi College of Agriculture and Nutrition, Mito, Ibaraki Prefecture, Japan, in 2004. To assess the suitability of this biotope as a habitat for insects, we surveyed the populations of odonate adults and aquatic insects (coleopterans, hemipterans, and odonate nymphs) in this biotope during 2006-2011. We observed 31 odonate species and at least 41 species of aquatic insects during this period. Thus, this biotope may provide a profitable habitat for these insects. The species richness, i.e., the number of species, of odonates and aquatic insects increased until 2007, and then decreased in 2008. This decrease may be attributed to the accumulation of mud at the bottom of the water bodies, which may deteriorate the quality of the habitat for aquatic insects. To recover habitat quality, we dredged up mud from the bottom of the water bodies in December 2008. Following 2009, the species richness of odonates and aquatic insects increased again. We estimate the process and factors responsible for the changes in the species richness of odonates and aquatic insects, and discuss some approaches for managing the biotope.

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Limnoporus esakii (Miyamoto) is a monomorphic macropterous water strider living on permanent fresh water bodies. Flight activity and flight muscle development in the adult water strider collected from the field were investigated to test for possibility of seasonal migratory flight. Morphological and physiological characteristics associated with seasonal flight activities were examined on the individuals reared under various photoperiodic conditions at 20℃. Only the overwintered or overwintering adults of L. esakii collected in mid-March, or late September and October flew. Percentages of individuals having well developed flight muscles were significantly higher in adults collected in mid-March and late September than those collected in April and July. Body size and wing area were larger in individuals reared under longer day-length conditions than shorter day-length ones. No significant difference was found in correlation coefficients between body length and wing area among individuals reared under different photoperiodic conditions. Wing loading was smaller in individuals reared under shortday conditions (13L11D and 10L14D) compared to those reared under a long-day condition (15L9D). Flight propensity and percentage of adults having well developed flight muscle tended to be higher in individuals developing under short-day conditions than those developing under the long-day condition. These results indicate that L. esakii exhibits flight muscle polyphenism caused by photoperiodic conditions, and seems to have a clear seasonality in the flight activities. These findings suggest migration between the water bodies and overwintering sites in fall and spring.

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We investigated the influence of the number of emerging adult females on egg density and magnitude of feeding damage caused by larvae of Fagineura crenativora Vikberg & Zinovjev. We evaluated seasonal changes in adult female emergence on Mount Tanzawa over a 3-year period, by using yellow flight-interception traps. In addition, we recorded egg density, feeding damage, and seasonal changes in leaf opening of Fagus crenata Blume. Adult females were trapped for approximately 1 month, with a peak occurring over 1-2 weeks. The total numbers of adult females trapped in 2007, 2008, and 2009 were 191, 75, and 162, respectively. During 2007 and 2008, the peak season for trapping adult females corresponded with the leaf-opening stage of Fagus crenata, when the leaves were suitable for egg laying. In 2009, the peak season for trapping adult females occurred at a later stage. The numbers of adult females trapped during the leaf-opening stages in 2007, 2008, and 2009 were 166, 51, and 11, respectively. In 2007, the egg density was 36 eggs per 100 leaves, and feeding damage was severe. By contrast, in 2008 and 2009, the egg densities were 3 eggs per 100 leaves and 4 eggs per 100 leaves, respectively, and feeding damage was mild. Our findings indicate that maximum feeding damage occurs when the peak season for adult female emergence corresponds with the leaf-opening stage of Fagus crenata, which is suitable for egg laying.

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Japanese Tit, Parus minor Temminck & Schlegel (Paridae), nest box was surveyed on June 9, 2012, in Yamato-son, Amami-Oshima Is., Japan. Although the nest box was colonized by ant, Tetramorium bicarinatum (Nylander) (Formicidae), over 191 moths of Monopis longella (Walker) (Tineidae) developed from the nest. This is the first report of moths and ants coexisting in the bird nest. The moth is not a myrmecophilous insect. It is inferred that the wall of nest materials well-tightened functioned as a barrier between the tineid larvae and ants. The ant touched the larva, but did not capture it. The moth larvae might have non-characteristic odor like myrmecophilous sylverfishes, and then ants did not attack them. The tineid larvae a little quickly burrowed into nest materials. This behavior may reveal to avoid being preyed upon by natural enemies (ant etc.).

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The website "Insects/Scientific Materials/Harmony Museum of Osaka Prefecture University" (http://www.museum.osakafu-u.ac.jp/html/jp/material/?mcat=1), which was awarded the Akitsu Prize 2012 by the Entomological Society of Japan, is introduced. The website consists of three categories, 1) General specimens, 2) Type specimens, and 3) Special exhibition. The contents include label and original reference data and photos of more than 300 type specimens (holotypes) of small moths (Microlepidoptera) and about 70 type specimens of fruit flies (Tephritidae etc.).

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