NOTES ON SUGAR FEEDING AND SELECTED WILD MAMMALIAN HOSTS OF BLACK FLIES (DIPTERA, SIMULIIDAE) IN NEWFOUNDLAND

This study, done on the Avalon Peninsula, Newfoundland, identified sel ected wild mammalian hosts and quantified the incidence of sugar feedi ng for several species (species complexes) of black flies. Female flie s were taken from fox, snowshoe hare, lynx, caribou, and human baits. Simulium truncatum/venustum complex females took blood from fox, lynx, rabbit, and caribou and,were frequently taken in sweep net collection s around humans. Blood-fed females, of the Simulium rostratum/verecund um complex were collected only from caribou, were rarely attracted to the other mammalian baits, and were not attracted to humans. Although most females had sugar-fed before seeking a host, significant interspe cific differences in the incidence of fructose-positive females were f ound among the four species (species complexes) examined (Prosimulium mixtum, 92.9%; S. truncatum/venustum complex, 87.4%; Stegopterna mutat a (triploid cytospecies), 83.3%; Simulium vittatum complex, 67.4%). No significant differences were found in the proportion of sugar-fed fli es among three habitats examined (forest, scrubland, and pasture) for either P. mixtum or the S. truncatum/venustum complex. However, the pe rcentage of sugar-fed S. truncatum/venustum complex females was signif icantly higher in the evening than in the morning. Time of day did not influence the incidence of sugar-fed P. mixtum.