WVBA beekeepers may recall meeting Dan Wyns. Dan, with Ellen Topitzhofer, has been the 2 person BeeInformed PNW Tech Team working out of Oregon State the past 3 seasons. Dan moved back to his native state to form a Michigan Tech Team this spring. The PNW Tech teams offer regular on-site hive inspections and sampling for large commercial beekeepers and queen breeders in OR, ID and WA.
Dan has written several blogs for BeeInformed. Five on Pollination (meadowfoam, cherries, watermelon, hybrid carrot seed and clover seed) are interesting, state-of-the-art information on how bees and PNW beekeepers provide pollination service to these crops. Other articles by Dan describe the OSU sentinel apiary, long hauling bees and top bar hives.
I invite you to read the most recent blog Dan recently posted to the BeeInformed website (See https://beeinformed.org/blog/) on drift.
In his language: “Bees have incredible navigation abilities that allow them to fly miles away from the colony to forage and return home with enough precision to locate the entrance to their colony, even when there are dozens of nearly identical hives within a small apiary site…… When a returning forager ends up returning to the wrong colony, she is typically not attacked as a robbing bee but accepted into the colony due to the pollen or nectar she carries. This process, known as drift, can lead to significant variations in colony strength over time and increase the potential for the spread of diseases and parasites within an apiary.”
Dan’s blog explains and illustrates how beekeepers may reduce drift through variation in hive color, arranging hives other than in straight-row patterns, considering colony orientation in the apiary and use of landscape features.
Dan concludes the blog with why beekeepers should pay more attention to drift: “Drift is not something that most beekeepers give a lot of thought and it is certainly not among the most critical factors impacting colony health. Nevertheless, there is a growing understanding of the impacts of horizontal transmission of varroa mites between colonies and the ability to control varroa levels within and between apiaries. Phoretic varroa on drifting foragers are one way that ‘clean’ colonies may become reinfested. Given the ever-increasing number of challenges to bee management, reducing drift represents one area where beekeepers can potentially reduce colony stress for a minimal amount of effort.”
In the PNW honey bee survey I ask what managements beekeepers are doing and include feeding, winterizing and hive sanitation questions. Check box choices under sanitation include “Providing hives with distinctive colors/ID” and “Spreading hives to reduce drifting”. When I analyzed the responses (and compared to loss rate) the two (of 6 choices) that had a loss level below the overall statewide average of 38% were these two choices: Statewide, 47 individuals (19%) who marked the reduced drifting option had a 31% loss rate and 76 respondents (31%) who indicated they practiced providing hives with color/ID had a 36% loss rate.
Among the 34 WVBA respondents (discounting the 9 that said they did none of the managements listed under sanitation, nor did they list anything else in the other box), 3 individuals (12%) said they took measures to reduce drifting by spreading colonies out and 11 persons (42%) indicated they provided their hives with distinctive color. The two most popular sanitation choices, Minimal hive intervention (140 individuals statewide (57%), 9 WVBA respondents -35%) and Generally avoided moving frames (99 statewide -40% and also 9 WVBA members) had loss levels statewide slightly higher than overall- 50% loss level for those not moving frames and 47% for those who practiced minimal hive intervention.
Dan’s blog provides good information on drifting. Obviously a good number of OR and WVBA beekeepers do seek to reduce drifting and use distinctive hive ID as a tool. It is important bees return to their own colony. Some colonies (mite bombs) that have high mite numbers show stressed, sick adults and are a high risk to potentially spread mites and virus to other colonies. The survey points out we can do more to get closer to our hoped-for result of reduced overwintering losses.