We made a survey of biting midges in Aomori Prefecture, mainly in the Mutsu area between 1986 and 1987, resulting in the confirmation of 16 classified and four unclassified types.In the Mutsu area, as many as 14-20 species were identified.In terms of distribution of biting midges in Aomori Prefecture, old-northern species in common with those in Europe and in Siberia were observed in large number.However, the species and the number of midges varied depending on the site of collection.To roughly classify the predominant species of biting midges by area,
C. sinanoensis, C.sanguisuga, and
C.maculatus were predominant in Tsugaru and Sanpachi areas (Aomori, Hirosaki, Kizukuri and Hachinohe), while
C. punctatus and
C. erairai were predominant in Shimokita area (Mutsu).In Kamitosan area, the distribution seemed to be in-between that of both divisions.
The data obtained from the 2-year continuous survey in Higashidori-mura and Ohma-machi were totalized and analyzed in order to evaluate the correlation between the number of biting midges and the temperature.As the result, in six species of biting midges including C.punctatus, significant positive correlation was observed at the risk ratio of 1 or 5%, and this analysis made it possible to estimate the temperature at the time of appearance of biting midges. And, it was estimated that biting midges appear at the mean temperature 16-17°C, the maximal temperature 19-20°C, and the minimal temperature 13-14°C.Furthermore, the appearance period was estimated from the temperature for the time of appearance, and C.punctatus gave the longest period of appearance, from mid or late June to late September or early October, while the others appeared between mid June and mid or late September.These results were in general agreement with the findings obtained from actual collection of biting midges.
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