Black flies (Diptera: Simuliidae) from Hardwicke Island, British Columbia

Abstract

Nineteen species of immature simuliids (Diptera: Simuliidae) were collected from streams on Hardwicke Island in the Johnstone Straits of British Columbia. These species were Simulium aureum Fries, S. canadense Hearle, S. decorum Walker, S. hunteri Malloch, S. tuberosum Lundström complex, S. venustum Say – verecundum, Stone and Jamnback complex, Prosimulium dicum Dyar and Shannon, P. esselbaughi Sommerman, P. formosum Shewell, P. travisi Stone, Simulium anatinum Wood, S. bafftnense Twinn group, S. bicorne Dorogostajskij, Rubtzov and Vlasenko complex, S. gouldingi Stone, S. piperi Dyar and Shannon, S. pugetense (Dyar and Shannon), S. vernum Macquart complex, Prosimulium doveri Sommerman, and Stegopterna sp. Enderlein. The last nine species have not been reported previously from British Columbia. Species composition, succession, and seasonal abundance of larvae and pupae were determined from April to August of 1980 and 1981. Simulium venustum–verecundum complex and S. hunteri were the most abundant species in 1980, while S. hunteri and S. vernum complex were most abundant in 1981. Black fly productivity was greatly reduced in 1981.

Apparent absence of blood parasites in Winter Wrens in British Columbia

“…It is improbable that a lack of vectors or inappropriate environmental conditions explains the lack of infection by hemoparasites in the Winter Wrens in our study. Vectors for hematozoa transmission are abundant in our study area (Greiner et al 1975b, Williams et al 1980, Mahrt 1982), and we conducted our study during the breeding season when vectors are most abundant and transmission most likely (Richner et al 1995, Allander and Sundberg 1997). Moderate rates of infection were also found in two sympatrically breeding species, suggesting that host–parasite assemblages may be present in our study area.…”

“…Four families in the order Diptera (Ceratopogonidae, Hippoboscidae, Simuliidae, and Culicidae) are intermediate hosts for transmission of hematozoan parasites in North American birds (Greiner et al 1975b, Mahrt 1982). These vectors are common in the Pacific Northwest region of North America (Greiner et al 1975b) and, therefore, we expected to find wrens infected by Plasmodium , Haemoproteus , Leucocytozoon , and Trypanosoma .…”