All-night man-biting collections of Anopheles farauti s.l. were made in a village in coastal Papua New Guinea in August and September 1982. A total of 10,827 mosquitoes were collected, and 6,293 of these were dissected for parity determination. The biting cycle varied according to moon phase, with more mosquitoes collected during the moonlit hours of the night. Parous mosquitoes also had a different biting cycle than nulliparous ones, but there was no interactive effect between age and moonlight. The overall number of mosquitoes biting was lower during moonless nights compared to nights when the moon was rising or full. A similar result was obtained in 1983 when 22,550 mosquitoes were collected over a 10-wk period from August to October. The proportion of human-fed females among engorged specimens collected while resting increased during moonless periods.