SummaryMarked drones (25 diploid and 22 haploid) were released in a colony, and observations on the duration of their flights were carried out for 5 hours per day on 8 days between 19th May and 5th June. Twenty diploid drones left the hive but only 5 returned, whereas 11 haploid drones flew and all returned. The 5 diploids which returned made a total of 13 flights, varying between 10·5 and 55 minutes in duration (mean 26·3±15·18 min); the 11 haploide made 17 flights (range 4·0–30·0 min, mean 15·0±6·73 min).