A survey of tabanid flies in Okushiri Island, Hokkaido, Japan

Abstract

The tabanid fauna of Okushiri Island, Hokkaido, Japan, was surveyed by collecting female adults with a mosquito-net trap baited with dry ice and by digging larvae and pupae with hand shovels, on August 6 and 7,1983. A total of 544 female adults of 9 species belonging to 3 genera and 39 immatures of 3 species of Tabanus were collected. Tabanus nipponicus, T. chrysurus and T. trigeminus were ubiquitous and predominant. The faunal make-up of this island with a considerable abundance of anautogenous tabanid population markedly differs from that of Rishiri and Rebun Islands. The influence of the livestock farming for the establishment of the tabanid fauna of this island was discussed.