Sister queen honeybees (Apis melli/era), 59 instrumentally inseminated (lIS) and 59 naturally mated (NM), were produced in Baton Rouge, Louisiana, and put into field colonies at 3 locations in Alberta, Canada and at 1 location in Louisiana, USA. Survival of the lIS queens was lower than that of the NM queens; 37 lIS queens and 50 NM queens survived from August 1981 to May 1982, and 18 lIS and 34 NM queens survived until August 1982 (P<O·Ol). At all 4 locations, the colonies with NM queens had 21-73% more capped brood in May (February in Louisiana) than did colonies with lIS queens (P<0·01). Probably because of this difference in brood production, the ,colonies with NM queens produced more honey. Over a l2-month period, the mean loss of spermatozoa from lIS queens was 0'9 million (28% of the original number in the spermatheca), and the mean loss for NM queens was 1'5 million (27%).