The activity of nine species of biting midges aspirated from cattle was recorded in the late afternoon, evening and early morning at a site near Darwin, Northern Territory, between March and June in 1999 and 2001. There were no significant differences between the temporal activity patterns for nulliparous and parous females of any species. Nulliparous females dominated collections of all species except Culicoides marksi. C. actoni and Forcipomyia (Lasiohelea) sp., were mostly active during daylight hours while C. peregrinus, C. bundyensis and C. brevipalpis, were nocturnal. Differences in the peak activity of C. brevitarsis were noted between years and occurred slightly earlier than that observed at other sites. C. fulvus, C. marksi and C. oxystoma were generally crepuscular but differed in the length and peak period of activity. C. actoni was four times more active in the evening than in the morning while C. marksi and C. peregrinus, were respectively 2.6 and 3.4 times more active in the morning than in the evening. Numbers of the other six species were not significantly different in the evening and morning. All nine species were collected at least once from cattle shortly after dawn.