Tracking Drone Drift Between Hives in an Apiary
The drifting of honey bees between hives in an apiary is a widely accepted, but little studied phenomenon. It is known to be a large contributor to the spread of disease between colonies; however, few preventative measures can be taken to curb this natural consequence without further understanding of the bees’ movement patterns. This study tracks the drifting of drone bees from four distinct colonies within an eight-colony apiary. Drone bees were selected as the subject for monitoring because they do not possess sting organs and their large bodies serve as reservoirs and transporters of the parasitic Varroa mite – an endemic arachnid responsible for much of the United States’ annual colony loss. Common belief in the beekeeping community is that the hives located on the ends of rows tend to be the strongest, and this theory has been supported by personal observation in the Oliver Apiary. Based upon this theory, we hypothesized that the hives with the most positive drifting behavior, denoting the influx of bees into the hive, would be Hives 1, 4, 5, & 8 because of their location on the row ends (Fig. IV).
This study was conducted over a six-week period in the Oliver Apiary through June and July of 2021. During the summer months, bee populations and activity are high – factors assumed to positively contribute to the frequency of drifting. 50 drone bees were hand-collected from each Hives 1, 4, 6, & 7 and tagged with colors blue, red, green, and yellow, respectively (Fig. IV), for a total of 200 sampled drones. Paint markers were used to color the abdomen or thorax of each bee as an indicator of their initial hive location (Fig. I). Counts of colored drones in each hive were taken during the standard hive inspections, so as not to disturb the usual activities of the colonies more than needed. These inspections occurred at most twice per week, though at request of the instructor, not every hive was investigated each week; it was entirely dependent upon the needs of the individual colony at that time. Were this study to be replicated, a stricter inspection schedule should be followed for more accurate results.
Positive drifting behavior was observed in six out of eight studied hives. Hive 5 had the largest occurrence of positive drifting, with a total of 13 foreign drones documented. Hive 1, also a row end hive, had a positive drift count of two and a negative drift (drone efflux) count of two. Hives 2 & 7 each had a positive drift count of three, and Hives 3 & 6 had a count of two. Hives 6 & 7 each had significant drone efflux counts of eight and ten, respectively. No drift was recorded for Hives 4 & 8 (Fig. III). Notably, the data displays a distinct westward drifting tendency, with only Hive 1 showing negative eastward drift (Fig. IV).
The positive drift count of 13 as observed in Hive 5 is consistent with our hypothesis that the hives on the end of the row would display the highest incidence of positive drift. This stands in contrast to the other row end hives which had positive drift counts of two (Hive 1) and zero (Hives 4 & 8) – numbers comparable to the counts observed in the middle row hives (Hives 2, 3, 6 & 7). Additionally, an unexpected trend of westward drifting is displayed at a higher occurrence rate than positive drift to row end hives. Further study is needed to verify these findings and possibly formulate practical applications to reduce disease spread by honey bee drifting.