The following was presented at the 2010 American Bee Research Conference in Orlando, FL.
6. Delaplane, K.S. & J.A. Berry – A TEST FOR SUB-LETHAL EFFECTS OF SOME COMMONLY USED HIVE CHEMICALS, YEAR TWO – We are involved in a two-year, two-state (GA, SC) experiment examining sub-lethal effects of selected bee hive chemicals; the list includes registered products at label rates as well as two off-label formulations. The reason we are doing this is that there is evidence that some of the chemicals used in beekeeping are hazardous to bees and contribute to bee decline (Frazier et al., 2008 Am. Bee J. 148(6):521-523; Desneux et al., 2007 Ann. Rev. Entomol. 52:81-106). Understanding this piece of the CCD puzzle will help beekeepers move toward more chemical-independent management. Here are results for two years from Georgia. Varroa levels (mites / 100 bees) were significantly higher in CheckMite (coumaphos)-treated colonies than in colonies treated with Taktic (amitraz); mite levels were intermediate in all other treatments. Bees in the non-treated control colonies exhibited numerically highest brood viability, homing ability, and foraging rate and numerically lowest incidence of queen supersedure cells. Information like this is important for evaluating the cost : benefit ratio of using exotic chemicals in honey bee management.
Table – Comparison of sublethal effects of various chemicals commonly used in hives.
|
Chemical |
Mites per 100 adult bees |
Brood viability (% open brood alive after 3 d) |
Supersedure cells |
Homing ability *1 |
Foraging rate *2 |
|
Non-treated |
11±2 (22)ab |
96.6±0.9(33) |
0.5±0.3(35) |
17±2.5(8) |
57±9(32) |
|
Cu naphthenate *3 |
13±2(19)ab |
89.2±2.7(30) |
2.2±0.7(32) |
10.4±2(7) |
54±8(29) |
|
Apistan (fluvalinate) |
7±1.4(21)ab |
92.8±1.4(31) |
3±1(33) |
16±2(6) |
52±8(30) |
|
CheckMite (coumaphos) |
14±2.6(20)a |
90.1±2.4(30) |
3.3±1(32) |
9.5±2(6) |
51±7(29) |
|
Maverik (fluvalinate) |
5±1.3(19)ab |
90.5±2.2(29) |
1.4±0.6(30) |
13.9±3(7) |
53±7(29) |
|
Taktic (amitraz) |
3±1(22)b |
91.3±2.1(29) |
2.1±0.5(34) |
15±7(7) |
50±7(31) |
- Reported as % of bees (of 30 marked) returning to colony entrance within 15 min after being released 1 km distant.
- Reported as number of foraging bees returning to colony entrance per min in observation period of 15 min.
- Copper naphthenate wood preservative was applied as a 2% water-soluble solution on a plywood panel which was allowed to air-dry and placed on hive floor.
More presentations from this conference can be found at Proceedings of the American Bee Research Conference 2010